Infantile cortical hyperostosis (Caffey disease) is a rare self-limiting inflammatory bony disease of early infancy. We report a 1-month-old Chinese boy with Caffey disease who presented with painful swelling over his shins bilaterally. Physical abuse was initially suspected, but the radiological findings of periosteal thickening over multiple bones (particularly the mandible), symmetrical involvement, diaphyseal involvement with sparing of the epiphysis, made Caffey disease a likely diagnosis. This report highlights that infantile cortical hyperostosis is an important differential diagnosis for children suspected of being abused, and clinicians should have a high index of suspicion to avoid misdiagnosis.

Liver abscesses are commonly caused by Enterobacteriaceae and anaerobes. This report is of a patient with liver abscess with massive haemolysis and multiorgan failure caused by Clostridium perfringens. Despite the reportedly high mortality rate and poor prognostic factors, the patient eventually recovered with prompt treatment.

Torsion of the nongravid uterus is a rare but potentially fatal acute abdominal condition. The non-specific clinical presentation of this condition makes preoperative diagnosis difficult. We describe a patient with uterine torsion in whom the diagnosis was made using contrast-enhanced computed tomography with multiplanar reconstruction. Features of uterine torsion and its complications can be demonstrated by computed tomography, which is an important means of making a preoperative diagnosis.

Liver abscesses caused by community-acquired methicillin-resistant Staphylococcus aureus are rarely reported. We report such a case in a 25-year-old man who presented with an intermittent fever. He had a history of prolonged antibiotic use for acne and skin abscesses. The liver abscess was successfully treated with percutaneous drainage and a prolonged course of linezolid. To our knowledge, this is the first reported case of a community-acquired methicillin-resistant Staphylococcus aureus liver abscess in Hong Kong, demonstrating the increasing threat posed by this multidrug-resistant organism. This case also suggests that a different epidemiology and route of infection may apply to community-acquired methicillin-resistant Staphylococcus aureus liver abscesses in contrast to the more common pyogenic liver abscesses.

Isovaleric acidaemia is a rare inherited organic acidaemia associated with a characteristic odour in affected patients. Fewer than 40 causative mutations have been reported to date. We report a case in a Hong Kong Chinese neonate who presented with respiratory distress and acute encephalopathy requiring aggressive resuscitation and treatment. Residual gross motor developmental delay was still observed at the age of 16 months. The child was subsequently found to harbour a known missense mutation (c.A1199G [p.Y371C]) and a novel 4-bp duplication (c.1148_1151dupGCTA [p.Y355X]) in the IVD gene. We suggest that the former is a founder mutation in the Chinese population and propose an explanation for the duplication event. Strategies that may achieve early diagnosis and prompt treatment include raising awareness of this condition, implementation of a tandem mass spectrometry neonatal screening programme, and local acquisition of appropriate medications for these metabolic diseases.