In July 2017, a 28-month-old boy presented to a private outpatient clinic with a 2-day history of fever and coryzal symptoms (Table). He had enjoyed good past health and his family history was unremarkable. On clinical examination, he was noted to have respiratory distress and tachycardia. Plain radiograph of the chest (CXR) showed perihilar haziness but no consolidation. He was transferred to Queen Mary Hospital, Hong Kong, to exclude myocarditis in view of elevated serum troponin in blood taken in the private clinic. On admission, he was noted to have diffuse crepitations and wheeze suggestive of pneumonitis. Nebulised salbutamol, hypertonic saline, and intravenous cefotaxime were administered. Complete blood count revealed neutrophilia, normal liver and renal function, and normal creatine kinase level. Venous blood gas showed no acidosis. Troponin was high initially but then gradually normalised. Echocardiogram showed no features of myocarditis. Nasopharyngeal aspirate and throat swab test results were positive for enterovirus (EV)/rhinovirus ribonucleic acid (RNA) using reverse transcriptase-polymerase chain reaction (RT-PCR) detection method. EV71 RNA was not evident. Nasopharyngeal aspirate for mycoplasma, throat swab and blood culture were all negative. He then developed progressive respiratory distress with increased cough and high fever up to 40°C on day 7 of illness and CXR showed worsening of bilateral perihilar haziness. In view of the progressive respiratory failure, the child was admitted to the paediatric intensive care unit 2 days later (day 9).

On admission to paediatric intensive care unit, he was noted to have generalised muscle weakness with a weak voice and an inability to sit up. Gag reflex and jerks were preserved. He was then intubated and ventilated under sedation. On reassessment, chest auscultation revealed decreased air entry over the left side, corresponding to the left lower zone collapse evident on CXR. He was prescribed piperacillin-tazobactam and levofloxacin. On day 10, throat swab culture grew only commensals while endotracheal aspirate revealed scanty growth of alpha-haemolytic streptococci with negative fungal smear and culture, and RT-PCR identified EV/rhinovirus. Broncho-alveolar lavage was also performed but results were unremarkable: Pneumocystis jiroveci (carinii), smear and culture for bacteria, fungus and acid-fast bacilli, and RT-PCR for cytomegalovirus, herpes simplex virus, Mycoplasma, Legionella, were all negative. Urine culture was negative for Legionella antigen.

On day 11, the patient exhibited paradoxical breathing on weaning of sedation along with hypotonia and paralysis of four limbs. Urgent sagittal T2-weighted magnetic resonance imaging of spine (day 11) showed mild T2 hyperintensity with mild expansion within the central portion of the cervical cord from C3 to C6 (Fig). No intraspinal mass or collection could be seen. Neurology examination was performed on day 12. Creatine kinase was normal and anti-acetylcholine receptor and anti-aquaporin-4 were negative. Eye examination the following day showed no evidence of optic neuritis. Immunoglobulin G and immunoglobulin M of anti-gangliosides were all negative. Lumbar puncture revealed normal cerebrospinal fluid level of glucose and protein. Total cell count was 100 × 10⁶/L with predominantly (80%) neutrophils. Cerebrospinal fluid culture was negative for viruses, including EV, herpes simplex virus or varicella-zoster virus. Cerebrospinal fluid levels of oligoclonal protein and immunoglobulin G were unremarkable. The working diagnosis was transverse myelitis affecting cervical cord C3 to C6. He was prescribed pulse methylprednisolone 30 mg/kg for 5 days (day 12 to 16) followed by a tapering oral dose of prednisolone together with intravenous immunoglobulin 2 g/kg over 2 days (day 16 and 17). He was also treated with therapeutic plasma exchange with 1.5-times plasma volume for five courses over 2 weeks (day 22, 24, 26, 30, 32). His condition gradually improved and he was extubated (day 47) after 38 days of invasive ventilation. The child was successfully discharged from the paediatric intensive care unit after 2 months (day 64) and achieved full neurological recovery with intensive training by physiotherapists. Subsequent review by a microbiologist using gene sequencing of initial specimens obtained on day 3 of admission to Queen Mary Hospital revealed EV-D68 RNA in nasopharyngeal aspirate, endotracheal aspirate and stool samples. Samples remained positive for 4 weeks (day 30, during acute deterioration warranting intensive care unit admission) and were negative after 6 weeks (day 55). The definitive diagnosis was EV-D68-associated acute flaccid paralysis (AFP) although EV-D68 was not present in the cerebrospinal fluid and plasma/serum samples were not tested for EV-D68 by RT-PCR.

Acute flaccid paralysis is defined by the World Health Organization as a clinical syndrome of diverse aetiology characterised by acute-onset limb weakness or paralysis with varying degrees of autonomic and somatic nervous system dysfunction that reaches maximum severity over a period of days or weeks in a child younger than 15 years of age.1 It is a diagnosis of exclusion. In 1962, a new strain of EV, EV-D68, was identified in Berkeley, California. In 2014, EV-D68 outbreaks were reported in 20 countries including the United States, Canada, Europe, and Asia with a total of over 2000 cases. This corresponded to an increased global incidence of AFP.2 A casual association between EV-D68 and AFP is supported by Bradford Hill criteria.3 Despite public health attempts in 1988 to eliminate AFP through the Global Polio Eradication Initiative4 and roll-out of the oral polio vaccine5 to prevent vaccine-associated poliomyelitis, the emergence of EV-D68-associated AFP has become a significant cause of neurological deficits in children since 2014. Owing to its impact on the healthcare system, a comprehensive literature review and further detailed studies are warranted. This is the first case encountered in our department. It is important for clinicians in Hong Kong to be alert for the disease.

As a newly emerging disease manifestation, a high index of suspicion and clinical awareness is advocated to facilitate earlier recognition and diagnosis through appropriate investigations, and presumably, improved clinical outcomes. The optimum treatment strategy has yet to be defined and preventive strategies are still being developed. Local and international notification systems as well as comprehensive surveillance are suggested since disease outbreaks may occur at any time and may have a serious impact on affected children.

Acquisition of data: WYK Chan, SHY Chim, DML Tse.
Analysis or interpretation of data: WYK Chan, DML Tse, PL Ho.
Drafting of the manuscript: WYK Chan.
Critical revision of the manuscript for important intellectual content: All authors.

All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

All authors have disclosed no conflicts of interest.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The parents of the patient gave consent for publication.

1. Bitnun A, Yeh EA. Acute flaccid paralysis and enteroviral infections. Curr Infect Dis Rep 2018;20:34. Crossref

2. Holm-Hansen CC, Midgley SE, Fischer TK. Global emergence of enterovirus D68: a systematic review. Lancet Infect Dis 2016;16:e64-75. Crossref

3. Messacar K, Asturias EJ, Hixon AM, et al. Enterovirus D68 and acute flaccid myelitis-evaluating the evidence for causality. Lancet Infect Dis 2018;18:e239-47. Crossref

4. World Health Organization. Global Polio Eradication Initiative. 2018. Available from: http://polioeradication.org/where-we-work/polio-endemic-countries/. Accessed 24 Mar 2018.

5. World Health Organization. Global Polio Eradication Initiative. Circulating vaccine-derived poliovirus. 2018. Available from: http://polioeradication.org/polio-today/polio-now/this-week/circulating-vaccine-derived-poliovirus/. Accessed 24 Mar 2018.

In January 2018, a 21-year-old man with good past health presented with a 2-week history of left forearm painless lump. He had no fever. The lump was 30 mm in diameter with no evidence of inflammation. Preoperative diagnosis was a sebaceous cyst and preoperative blood tests were not routinely performed.

Surgical excision was performed under local anaesthesia with lidocaine and application of a tourniquet. Intra-operatively, a whitish-yellowish 25-mm subcutaneous nodule surrounded by dense adhesions without a definite border was removed. The nodule was firm and multi-lobulated with multiple feeding vessels. Although en bloc excision with a 5-mm margin was attempted, the dense fibrous mass was partially breached during dissection due to scarring.

After tourniquet release, the patient developed flushing, dizziness, diarrhoea, hypotension, and sinus tachycardia. He had no respiratory distress but the clinical diagnosis was anaphylactic shock. He was stabilised with fluid resuscitation and intravenous adrenaline. Laboratory tests showed an elevated white blood cell count (WBC) at 13.6 × 10⁹/L (reference range: 3.9-10.7 × 10⁹/L), neutrophil predominance at 85.9% (reference: 38%-76%), and low eosinophil count of only 0.027 × 10⁹/L (reference: <0.45 × 10⁹/L) and 0.2% of total WBC. Blood tests were otherwise unremarkable. Serum mast cell tryptase level was 46.2 μg/L immediately after surgery but dropped to 3.3 μg/L after 24 hours. Erythrocyte sedimentation rate or C-reactive protein were not measured. The patient remained well and was discharged home the next day.

The patient had no known history of allergy and skin allergy test for exposed agents including lidocaine was negative. On further questioning, he revealed regular contact with horses located in a countryside barn but no contact with other animals. He reported skin erythema (Fig 1) prior to swelling onset but had presumed this was due to a mosquito bite.

Microscopy of the nodule revealed a piece of fibro-fatty tissue with mixed inflammatory cell infiltrate and dense eosinophilic infiltrate (Fig 2a), and a 0.72 mm × 0.29 mm fragment of degenerated parasite rimmed by foamy histiocytes (Fig 2b). There was no evidence of malignancy. The surgical margin measured from the edge of the surrounding granulomatous inflammation to the closest edge of the excised specimen was 0.82 mm. Further molecular study by polymerase chain reaction and DNA sequencing based on Filarioidea cytochrome oxidase subunit I (cox1) and specific 12S ribosomal RNA (12S rRNA) gene revealed the parasite to be Dirofilaria hongkongensis.1

The patient remained symptom-free and differential WBC and C-reactive protein were normal at 6 months after surgery. No antiparasitic therapy was deemed necessary by microbiologists.

Dirofilaria hongkongensis has been proposed as a novel species causing zoonotic filariasis in humans and is a possible cause of unresolved subcutaneous nodules in Hong Kong.2 This is the first reported case worldwide of anaphylactic shock following excision of subcutaneous dirofilariasis in a human.

Zoonotic filariae are transmitted to humans through the bite of an infected arthropod such as mosquitoes. However, they cannot grow to maturity in accidental hosts such as humans.3 The pathogenesis is localised foreign body reaction around a moribund parasite. The absence of a host inflammatory response in the asymptomatic period suggests death of the worm due to an unfavourable host environment, rather than host immunity.3 Asymptomatic survival and growth of the parasite may continue for ≥6 months. The lesion becomes clinically noticeable due to granulomatous reaction with tissue scarring and can present as a subcutaneous or ocular lesion, and rarely as lymphadenopathy and nodules in deeper tissues such as the lungs. In our patient, the subcutaneous dirofilariasis presented as a painless lump in his forearm, without any symptoms or signs of inflammation. The patient reported some skin erythema prior to the onset of the swelling. The erythema could have been caused by a mosquito bite, which is a possible route of parasite transmission. The absence of pain, warmth, or erythema over the mass would suggest the parasite did not trigger a significant inflammatory response in our patient. After the parasite’s death, the remaining material could be shielded off from the host tissue by a dense fibrous tissue envelope, producing a lump which was otherwise asymptomatic.

Careful history taking may reveal exposure to animals. Subcutaneous infections are small (0.5-1.5 cm) and discrete. Pain or sense of a moving worm may be present. Blood tests for eosinophilia and elevated inflammatory markers might be useful, but the absence of systemic inflammation is common3 and blood test results may be unremarkable. In our patient, blood tests were not taken preoperatively, as the clinical impression of the mass was a sebaceous cyst, with the absence of signs of inflammation. Postoperative blood tests showed neutrophilia instead of eosinophilia, but the results were likely affected by the anaphylaxis.

Among around 40 species of Dirofilaria, D immitis and D repens account for most cases of infection in humans. Dirofilaria immitis is commonly known as “dog heartworm” and has a cosmopolitan distribution. Hou et al4 reported seropositivity in 30.6% of stray dogs and 15.6% of domestic dogs in north-eastern China. Wang et al5 reported a 0% to 7.4% seroprevalence in dogs in coastal cities in south-eastern China. Dirofilaria repens is prevalent worldwide including Southeast Asia. Dirofilaria hongkongensis was first proposed as a distinct species in 2012, following three cases of human infection.2 In stray dogs in Hong Kong, the seroprevalence of D hongkongensis is 3%,2 and that of D immitis is 10%.6

Molecular study in nucleotide sequencing of cytochrome oxidase subunit 1 (cox1) gene and the 12S ribosomal RNA (12S rRNA) gene is useful in the identification of Dirofilaria species, taking reference from GenBank data. The cox1 gene and 12S rRNA gene specific to D hongkongensis were identified (GenBank accession number NC_031365). Simpler diagnostic tests would be less reliable; for example, morphological identification depends on the quality of histopathological specimen, and in our case only parasitic fragments were found. Retrospective molecular study could also be performed on the stored specimen for epidemiological studies.

Parasitic materials are foreign antigens that may trigger a type I immunoglobulin E–mediated hypersensitivity reaction. Dirofilaria immitis extract can result in shock and elevated plasma histamine level in dogs,7 while hydatid cyst (Echinococcus spp) rupture has been associated with anaphylactic shock.8 We believe the partial breach of the parasitic tissue envelope during our surgical dissection led to contact of parasitic material with host tissue. This contact, in turn, caused the hypersensitivity reaction and anaphylactic shock in our patient.

We recommend complete en bloc excision of lesions suspected to be caused by dirofilariasis to prevent anaphylaxis, especially when surgeons encounter dense adhesions or multiple feeding vessels. Further study is required to ascertain the necessary margin of excision to avoid inadvertent breakage of the tissue envelope. Up to 75.4% of parasitised humans experience chronic urticaria.9 In our patient, the capsule was breached during dissection and sudden allergen release may have triggered the anaphylactic cascade. Antiparasitic medication is likely unnecessary if the parasite can be removed intact.

Anaphylactic shock can cause sudden haemodynamic collapse. It is characterised by acute onset of hypotension after allergen exposure, or the combination of cutaneous, cardiopulmonary or gastrointestinal manifestations.10 The importance of routine monitoring, timely detection and cardiopulmonary stabilisation cannot be overemphasised. Plasma tryptase or histamine level may serve as a diagnostic adjunct in doubtful cases. Fluid resuscitation, supplemental oxygen, and epinephrine injection are indicated as effective treatments of anaphylactic shock.

All authors contributed to the concept of study, acquisition and analysis of data, drafting of the manuscript, and critical revision of the manuscript for important intellectual content. All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

All authors have disclosed no conflicts of interest.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The patient was treated in accordance with the Declaration of Helsinki. The patient provided verbal informed consent for publication of this de-identified case report, including clinical photos.

1. Dang TC, Nguyen TH, Do TD, et al. A human case of subcutaneous dirofilariasis caused by Dirofilaria repens in Vietnam: histologic and molecular confirmation. Parasitol Res 2010;107:1003-7. Crossref

2. To KK, Wong SS, Poon RW, et al. A novel Dirofilaria species causing human and canine infections in Hong Kong. J Clin Microbiol 2012;50:3534-41. Crossref

3. Eberhard ML. Zoonotic filariasis. In: Guerrant R, Walker D, Weller P, editors. Tropical Infectious Diseases: Principles, Pathogens, and Practice. 3rd ed. New York: Elsevier; 2011: 750-8. Crossref

4. Hou H, Shen G, Wu W, et al. Prevalence of Dirofilaria immitis infection in dogs from Dandong, China. Vet Parasitol 2011;183:189-93. Crossref

5. Wang J, Zhu X, Ying Z, et al. Prevalence of Dirofilaria immitis infections in dogs and cats in Hainan Island/Province and three other coastal cities of China based on antigen testing and PCR. J Parasitol 2019;105:199-202. Crossref

6. Wong SS, Teng JL, Poon RW, et al. Comparative evaluation of a point-of-care immunochromatographic test SNAP 4DX with molecular detection tests for vector-borne canine pathogens in Hong Kong. Vector Borne Zoonotic Dis 2011;11:1269-77. Crossref

7. Kitoh K, Katoh H, Kitagawa H, Nagase M, Sasaki N, Sasaki Y. Role of histamine in heartworm extract-induced shock in dogs. Am J Vet Res 2001;62:770-4. Crossref

8. Khanna P, Garg R, Pawar D. Intraoperative anaphylaxis caused by a hepatic hydatid cyst. Singapore Med J 2011;52:e18-9.

9. Minciullo PL, Cascio A, Gangemi S. Association between urticaria and nematode infections. Allergy Asthma Proc 2018;39:86-95. Crossref

10. Simons FE, Ardusso LR, Bilò MB, et al. World allergy organization guidelines for the assessment and management of anaphylaxis. World Allergy Organ J 2011;4:13-37. Crossref

A 51-year-old lady with a history of congenital diaphragmatic hernia repair during infancy presented to the emergency department with increasing abdominal pain and repeated vomiting. Posteroanterior chest plain radiograph revealed dilated small bowel loops in the right thoracic cavity. Computed tomography scan revealed two closely related small bowel loops trapped within a narrow hernia neck orifice across the diaphragm, suggestive of closed loop intestinal obstruction (Fig 1). Blood test results revealed metabolic acidosis and elevated lactate level.

Emergency laparotomy via a subcostal incision revealed a right-sided large diaphragmatic defect with bowel herniating into the thoracic cavity. Transabdominal reduction of the bowel was difficult owing to adhesion of bowel to the lung so an additional posterolateral thoracotomy was performed by a cardiothoracic team. Adhesiolysis was performed and the small bowel freed and reduced to the abdominal cavity via the transthoracic approach. Examination through the thoracotomy revealed minimal residual diaphragmatic tissue (Fig 2a). Primary closure was not possible and repair with a patch posed a technical challenge in the absence of sufficient residual diaphragmatic tissue to enable secure anchorage. For the anterolateral portion, multiple pledgetted 3-O sutures were passed through the intercostal space for anchorage (Fig 2b). A neo-diaphragm was reconstructed using a porcine dermal collagen implant of size 150 mm × 200 mm × 1 mm (Permacol^TM; Medtronic, Minneapolis [MN], United States). The patch was then parachuted down to cover the defect and secured. A 4-cm flutter-valve patch was directed downwards and medially to avoid suturing and injury to the oesophagus and inferior vena cava (Fig 2c). We believe this design permits peristalsis of oesophageal content without causing stricture while also preventing future intestinal herniation.

Postoperatively the patient was prescribed total parenteral nutrition for 10 days and gradually tolerated a normal diet. A computed tomography scan at 10 days after surgery confirmed an intact neo-diaphragm with no recurrence of hernia. The patient was discharged home 13 days after surgery. She was well at follow-up examinations at 1 month and 12 months after surgery. Chest plain radiograph confirmed no recurrence of hernia (Fig 3).

Diaphragmatic hernia is a rare but serious condition associated with respiratory and gastrointestinal complications and increased mortality.

Surgical repair is the gold standard treatment to prevent complications. However, patients with a previously repaired congenital diaphragmatic hernia are more prone to respiratory complications during childhood and occasionally develop recurrences.1 However, the long-term success rate of repair is good with patients surviving well into adulthood with a normal life expectancy.

Surgical options for repair include a primary repair and a patch repair. A patch repair is associated with higher risks of complications and recurrence.2 However, for a hernia with large defects in which a primary repair is not possible, repair with surgical mesh (xenograft or synthetic) is an effective and safe method.3 In conventional patch repair, the hernia sac is repositioned and resected. The hernia defect is sized and the Permacol trimmed to cover the defect. The flap is then fixed to the remaining rim of diaphragmatic tissue with absorbable sutures.4 The lack of an adequate rim of tissue in our patient presented a unique challenge for construction of the neo-diaphragm relative to most instances of diaphragmatic hernia where a remnant of diaphragmatic tissue is present for anchorage. Although the pleura and adjacent chest wall offer good support for anchoring the neo-diaphragm posteriorly and anterolaterally, there is often a lack of strong tissue medially with consequent substantial risk of inadvertent injury to the oesophagus if sutures are placed too deeply. Travers et al5 reported an incidence of oesophageal injury up to 3.9% in their series of surgical repair of para-oesophageal hernia using porcine dermal collagen biologic mesh (Permacol). Innovative designs in the creation of the neo-diaphragm have been reported, but most studies have been in paediatric patients.6 The technique described in this case report is novel and has not been reported elsewhere. The design of a flutter valve mechanism in the reconstruction of the medial aspect of the neo-diaphragm serves to create a tension-free repair near the mediastinum and oesophagus while also creating a seal to separate the pleural cavity from the abdominal contents. No sutures were applied near the oesophagus or the medial side of the neo-diaphragm. This technique avoids inadvertent visceral injury and is currently our preferred technique of neo-diaphragm construction in patients with a large diaphragmatic defect and insufficient rim.

In our case, we utilised the acellular dermal matrix Permacol for hernia repair. Permacol is a cross-linked graft comprised of acellular collagen matrix. Compared with other collagen-based implants, it offers long-lasting dimensional stability and avoids loss of tensile strength as well as increased tissue laxity resulting in lower rates of recurrence. Acellular dermal matrix is a developing technology and studies have shown promising results for its efficacy.7

In conclusion, repair of diaphragmatic hernia with a xenograft composed of dermal collagen implant and a medial flutter-valve design is safe and effective. It avoids inadvertent injury to mediastinal structures while allowing satisfactory prevention of recurrence of diaphragmatic herniation of intestines.

Concept or design: All authors.
Acquisition of data: All authors.
Analysis or interpretation of data: All authors.
Drafting of the manuscript: THY Wong, SCY Chow, RHL Wong.
Critical revision of the manuscript for important intellectual content: All authors.

All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

All authors have disclosed no conflicts of interest.

This study received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The patient was treated in accordance with the tenets of the Declaration of Helsinki. The patient provided written informed consent for all treatments and procedures and consent for publication.

1. Jancelewicz T, Chiang M, Oliveira C, Chiu PP. Late surgical outcomes among congenital diaphragmatic hernia (CDH) patients: why long-term follow-up with surgeons is recommended. J Pediatr Surg 2013;48:935-41. Crossref

2. Jancelewicz T, Vu LT, Keller RL, et al. Long-term surgical outcomes in congenital diaphragmatic hernia: observations from a single institution. J Pediatr Surg 2010;45:155-60. Crossref

3. Kuhn R, Schubert D, Wolff St, Marusch F, Lippert H, Pross M. Repair of diaphragmatic rupture by laparoscopic implantation of a polytetrafluoroethylene patch. Surg Endosc 2002;16:1495. Crossref

4. Lingohr P, Galetin T, Vestweber B, Matthaei H, Kalff JC, Vestweber KH. Conventional mesh repair of a giant iatrogenic bilateral diaphragmatic hernia with an enterothorax. Int Med Case Rep J 2014;7:23-5. Crossref

5. Travers HC, Brewer JO, Smart NJ, Wajed SA. Diaphragmatic crural augmentation utilising cross-linked porcine dermal collagen biologic mesh (Permacol) in the repair of large and complex para-oesophageal herniation: a retrospective cohort study. Hernia 2016;20:311-20. Crossref

6. Loff S, Wirth H, Jester I, et al. Implantation of a cone-shaped double-fixed patch increases abdominal space and prevents recurrence of large defects in congenital diaphragmatic hernia. J Pediatr Surg 2005;40:1701-5. Crossref

7. Buinewicz B, Rosen B. Acellular cadaveric dermis (AlloDerm): a new alternative for abdominal hernia repair. Ann Plast Surg 2004;52:188-94. Crossref

In July 2020, a 35-year-old pregnant woman (weight 70 kg, height 160 cm, body mass index 27.3) at 34+3 weeks of gestation presented to our hospital with upper respiratory tract infection symptoms including dry cough and runny nose for 4 days. The patient had a history of lower segment caesarean section in 2016, with good past health and an unremarkable antenatal history. Reverse transcription polymerase chain reaction analysis of the patient’s deep throat saliva sample was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The cycle threshold value was 19.79 indicating a high viral load. She had no fever or shortness of breath at any time.

The patient also presented with a small amount of per-vaginal spotting but had no abdominal pain or leaking sensation. Fetal movements were active. The patient’s blood pressure was 98/62 mm Hg, pulse was 97 bpm, SpO₂ was 97% on room air, and body temperature was 37°C. Fetal ultrasonography was unremarkable with appropriate size for gestational age. The impression was of antepartum haemorrhage of unknown origin and maternal coronavirus disease 2019 (COVID-19) infection.

The patient had normal liver and renal function, clotting profile and chest radiograph, and negative results for influenza A/B and respiratory syncytial virus tests. Other results included: haemoglobin 11.1 g/dL, platelet count 198×10⁹/L, neutrophilia of 73% white blood cell differential count, lymphopenia at 0.9×10⁹/L 16.5% of white blood cell differential count, and C-reactive protein 8 mg/L (ref <5 mg/L).

The patient was admitted to a negative pressure isolation ward, standard practice for airborne infection. A multidisciplinary meeting was held involving obstetricians, anaesthesiologists, paediatricians, microbiologists, infectious disease specialists, and intensivists. The consensus, agreed with the patient, was that an early elective lower segment caesarean section under spinal anaesthesia should be performed the next day.

Routes were isolated and protected for transferring patients between the operating theatre (OT), the isolation ward, and the neonatal intensive care unit, and for transferring healthcare workers from the OT to decontamination shower facilities. Only essential equipment, medications, and consumables were placed inside the OT. Disposable consumables were used whenever possible. Paper records were minimised and sealed.

Preparations were made inside the OT for spinal anaesthesia, and for conversion to general anaesthesia if necessary. Medications for induction and resuscitation were prepared in advance, including propofol, succinylcholine, cisatracurium, phenylephrine, ephedrine, atropine, neostigmine, syntocinon, carbetocin, and tranexamic acid. A video laryngoscope with disposable blades, stylet, elastic gum bougie, endotracheal tubes and size 3 and 4 classic and supreme laryngeal masks were placed under plastic sheet covers.

Staff exposure time was minimised, but this was balanced against an optimal standard of patient care. Only active essential personnel were present in the OT for each stage of surgery. All staff inside the OT wore level 3 personal protective equipment, including fluid-resistant long-sleeve gown, gloves, face shield, and fit-tested N95 masks according to airborne precautions. During spinal anaesthesia, only two anaesthesiologists and an assistant were present in the OT. The anaesthesiologists wore water-resistant sterile gowns during the spinal anaesthesia. Other staff, including the surgeons and midwives, waited in the anteroom entering the OT only when the anaesthesia was complete.

The patient wore a water-resistant surgical mask throughout the transfer and surgery. She required no supplementary oxygen. On entering the OT, her blood pressure was 120/82 mm Hg, pulse 91 bpm, and SpO₂ 99.4% on room air. Anaesthesia was induced by 2.2 mL of 0.5% hyperbaric bupivacaine, 15 μg of fentanyl, and 0.15 mg morphine injected intrathecally via a 25-gauge pencil tip spinal needle in a single attempt, at the L3-L4 level, with sensory block to T5 bilaterally. Phenylephrine (100 μg/mL) infusion at 15 mL/h (0.36 μg/kg/min) was commenced 5 minutes after spinal anaesthesia. A baby girl was delivered 19 minutes after the spinal injection. Total blood loss was 1000 mL, and 2000 mL of Plasma-Lyte A was infused. A phenylephrine infusion was titrated down and stopped on completion of the surgery. The patient’s blood pressure was 116/56 mm Hg and her pulse was 68 bpm. Monitoring continued in the same OT to avoid contamination of the post-anaesthesia care unit.

Postoperative analgesia included oral paracetamol 1 g four times daily and diclofenac sodium sustained release 100 mg daily. The patient was followed up daily. She was satisfied with the overall anaesthetic experience and pain control. The baby had 1-minute and 5-minute Apgar scores of 8. Repeated tests of nasopharyngeal aspiration and throat swab were negative for SARS-CoV-2 infection; however, the patient was nursed in an isolation ward in the neonatal intensive care unit as a precaution.

Samples including amniotic fluid, placental swab, high vaginal swab and breast milk all tested negative for SARS-CoV-2. All personnel directly involved in care of the mother and the baby and those involved in OT decontamination remained symptom free after 14 days of medical surveillance.

The timing of delivery was a major concern for this patient. If the mother’s health had deteriorated before delivery, the use of certain antiviral medications would have caused deranged organ function and affected fetal well-being. Corticosteroid may have harmed the mother.1 2 Use of corticosteroids in preparation for premature labour is thought to cause a worse outcome in patients with COVID-19.3 Fortunately our patient was at >34 weeks’ gestation. Unexpected deterioration of the mother’s health could also result in the need for an unanticipated urgent operative delivery, imposing increased operative risks, as well as increased infectious risks to healthcare workers. In particular, general anaesthesia requires endotracheal intubation that is considered an aerosol-generating procedure. Spinal anaesthesia offered a good alternative to general anaesthesia in a planned setting, as illustrated by a case series from Wuhan, China, of 49 caesarean deliveries with good blood pressure control achieved under spinal anaesthesia.4

Early data suggest that pregnant women do not develop more severe COVID-19.5 In a study of 241 births in the United States, approximately 30% of mothers with COVID-19 became symptomatic, 7.1% required intensive care unit admission, 3.7% required intubation, and 0.7% progressed to a critical condition. The deterioration could be rapid and occurred over a variable time frame.5 Current guidelines suggest that COVID-19 infection by itself is not an indication for early induction of labour or operative delivery, but that the timing of delivery should be determined by obstetric indications.6

This patient presented with antepartum haemorrhage of unknown origin, and minor placental abruption could not be excluded. Any deterioration in placental abruption could rapidly jeopardise the well-being of the fetus and mother. The decision for early elective operative delivery was appropriate in these circumstances.

Concern was expressed about high viral load and infectivity, given the patient’s high cycle threshold value of 19.79. However, there is wide variation in the interpretation of cycle threshold,7 and no evidence that a lower cycle threshold value correlates with worse prognosis.8

This case report confirms that it is possible for a patient with confirmed SARS-CoV-2 infection to safely undergo spinal anaesthesia with maintenance of stable blood pressure.4 Our findings suggest that pregnant women with mild COVID-19 symptoms are little different to healthy pregnant women who undergo spinal anaesthesia for caesarean section.

Overall, this case report demonstrates that with the input of anaesthesiologists, joint clinical decisions and effective communication between relevant specialties, a well-planned and rehearsed routing, and correct use of personal protective equipment, the infectious risks to health care professionals could be minimised while providing an appropriate standard of care to the mother and the baby.

All authors contributed to the concept or design of the study, acquisition of the data, analysis or interpretation of the data, drafting of the manuscript, and critical revision of the manuscript for important intellectual content. All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

The authors declare that they have no conflict of interest.

This case report received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The patient was treated in accordance with the tenets of the Declaration of Helsinki. The patient provided written informed consent for all treatments and procedures.

1. Sanders JM, Monogue ML, Jodlowski TZ, Cutrell JB. Pharmacologic treatments for coronavirus disease 2019 (COVID-19): a review. JAMA 2020;323:1824-36. Crossref

2. Bauer ME, Bernstein K, Dinges E, et al. Obstetric anesthesia during the COVID-19 pandemic. Anesth Analg 2020;131:7-15. Crossref

3. Society for Maternal-Fetal Medicine, Society for Obstetric and Anesthesia and Perinatology. Labor and delivery COVID-19 considerations. Available from: https:// s3.amazonaws.com/cdn.smfm.org/media/2402/SMFM-SOAP_COVID_LD_Considerations_-_revision_6-16-20_PDF.pdf. Accessed 26 Jul 2020.

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In areas endemic for tuberculosis infections, the presence of infection on imaging and granulomatous inflammation on histology is often sufficient to start antituberculous pharmacotherapy. However, this may not be appropriate in cases of non-tuberculous granulomatous infection. Rarer causes of spinal infection should be considered, especially if the clinical response is suboptimal. We present an unusual case of granulomatous spinal infection caused by Coxiella burnetii.

A 74-year-old man from southern China with no travel history presented with a 3-month history of low back pain in the absence of neurological deficit or constitutional symptoms. Co-morbidities included hypertension, diabetes mellitus, and hyperlipidaemia. There were no symptoms or signs of endocarditis. Initial plain radiographs showed lytic destruction of L4 and erosion of the L4-L5 disc space. Laboratory investigations revealed raised C-reactive protein (CRP) of 27.6 g/dL and erythrocyte sedimentation rate of 32 mm/h. Blood culture, Widal test for Salmonella, HIV testing and acid-fast bacilli growth in sputum and blood were all negative. There was no growth of fungus or brucellosis. Magnetic resonance imaging and computed tomography (CT) revealed L4/5 spondylodiscitis with psoas and paravertebral abscesses (Fig 1), and a mycotic infrarenal abdominal aortic aneurysm measuring 7.3 × 7.6 × 5.7 cm. He underwent endovascular stenting of the aneurysm. A CT-guided aspiration of the psoas abscess was negative on Ziehl–Neelsen and Grocott staining and tuberculous polymerase chain reaction. Histology confirmed granulomatous inflammation. After discussion with the microbiologist, the patient was prescribed intravenous ceftriaxone 2 g per day and metronidazole 1 g per day but switched to ertapenem 1 g per day due to a poor clinical response. These antibiotics were used as empirical therapy. Symptoms subsided and his CRP normalised to <0.35 g/dL. He was discharged home and prescribed lifelong amoxicillin/clavulanic acid 375 mg 3 times daily, with levofloxacin 500 mg once daily for the mycotic aneurysm.

At 6 months after discharge he presented with recurrent back pain along with radicular symptoms. Inflammatory markers were elevated with CRP 3.5 g/dL and erythrocyte sedimentation rate 81 mm/h. The same cultures and serology were negative. Plain radiographs and CT showed increased bony destruction of L4. Magnetic resonance imaging revealed persistent retroperitoneal abscess with progressive spondylodiscitis (Fig 2). A CT-guided drainage of his right psoas abscess yielded negative culture results. Due to the neurological deterioration, an L3-L5 laminectomy with posterior instrumented spinal fusion was performed. Anterior column reconstruction was attempted by the vascular surgeon but scarring prevented safe access to the spinal column without aneurysmal injury. The L4-L5 disc material revealed granulomatous inflammation and methicillin-resistant Staphylococcus aureus. He was treated as co-infection with tuberculosis and methicillin-resistant Staphylococcus aureus, and was given isoniazid 300 mg, rifampicin 450 mg, and ethambutol 800 mg once daily, and linezolid 600 mg every 12 hours. His inflammatory markers normalised but back pain persisted.

Serial radiographs showed implant failure with further destruction of L4 (Fig 3) due to the lack of anterior column support. Revision posterior instrumented fusion was performed 3 months after the initial surgery from T10 to the pelvis with cement augmentation after removal of the loosened L3-L5 implants. Intra-operative findings were friable tissue and osteoporotic bone. Histology still showed granulomatous inflammation but other cultures were negative. Due to the persistent infection with negative cultures, serology for C burnetii was performed and revealed increased phase I and phase II polyvalent antibodies with titre results of 3200 for both. The patient was diagnosed with chronic Q fever and was given lifelong hydroxychloroquine sulphate 200 mg every 8 hours and doxycycline hyclate 100 mg every 12 hours owing to the presence of the endovascular stent and spinal instrumentation. Serial monitoring of Q fever serology was performed every 6 months. At 2 years after surgery, he remains symptom free with no implant loosening.

First described in 1937, Q fever is caused by C burnetii and can be found worldwide with an overall prevalence of 10%.1 2 Inoculation is through direct contact, ingestion or inhalation of contaminated materials. Traditionally it is thought that contact with cows, goats, sheep or cats causes this disease, but it is not always the case. In chronic Q fever, endocarditis is the most common presentation, seen in 60% to 70% of cases. Other manifestations include hepatitis, pericarditis, myocarditis, vascular infections, and osteoarticular infection.3 Diagnosis is usually by serological testing but can also be on smears or frozen tissue with Giemsa staining that reveals doughnut granulomas. Although serology shows only indirect evidence of infection, it is a simpler and reliable technique. In acute Q fever, testing is performed for antibodies against phase II antigens. In chronic Q fever, testing is for antibodies against phase I antigens. Diagnosis is confirmed if immunoglobulin G titre exceeds 1/800. Cultures are not commonly performed due to its high infectivity and is not available in our laboratory.

Osteoarticular Q fever infections are rare. One study from France showed that only 7.3% of all their patients with Q fever manifested with osteoarticular infection.4 The most common form of Q fever osteoarticular infection is chronic osteomyelitis. This is usually a result of contamination from a previous open fracture or prosthetic joints and vascular grafts.4 Adults usually present with an infected prosthetic joint and children with multifocal osteomyelitis.1

A review of this case revealed that the patient had previously travelled to Guangdong province in China and had contact with farm animals. This was the only potential source of infection from his history. A high index of suspicion is needed for diagnosis, as seen in this case, because a delay in treatment can lead to multiple surgeries. Despite being in an endemic area for spinal tuberculosis,5 other rarer causes of spondylodiscitis with granulomatous inflammation must be considered. These include other bacteria such as Brucellosis, melioidosis, actinomycosis, and Bartonella infections. Spirochetes, fungi, toxoplasmosis, and viruses such as infectious mononucleosis, cytomegalovirus, measles, and mumps are also potential causes. The presence of endovascular infection with spondylodiscitis with granulomatous inflammation and negative cultures should raise the alarm for potential Q fever. Patients are commonly misdiagnosed and treated with prolonged antimicrobials and surgery without improvement.

Concept or design: JPY Cheung.
Acquisition of data: All authors.
Analysis or interpretation of data: All authors.
Drafting of the manuscript: All authors.
Critical revision of the manuscript for important intellectual content: JPY Cheung.

All authors had full access to the data, contributed to the study, approved the final version for publication, and take responsibility for its accuracy and integrity.

As an editor of the journal, JPY Cheung was not involved in the peer review process. Other authors have disclosed no conflicts of interest.

This case report received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

The patient was treated in accordance with the Declaration of Helsinki and provided informed consent for all treatments and procedures and consent for publication.

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2. Fantoni M, Trecarichi EM, Rossi B, et al. Epidemiological and clinical features of pyogenic spondylodiscitis. Eur Rev Med Pharmacol Sci 2012;16 Suppl 2:2-7.

3. Landais C, Fenollar F, Constantin A, et al. Q fever osteoarticular infection: four new cases and a review of the literature. Eur J Clin Microbiol Infect Dis 2007;26:341-7. Crossref

4. Melenotte C, Protopopescu C, Million M, et al. Clinical features and complications of Coxiella burnetii infections from the French National Reference Center for Q fever. JAMA Netw Open 2018;1:e181580. Crossref

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