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.

Immunoglobulin G4–related lymphoplasmacytic sclerosing disease is an emerging disease. Recently, it has been shown to be responsible for autoimmune pancreatitis-induced strictures of the bile duct mimicking cholangiocarcinoma. Making a diagnosis of immunoglobulin G4–associated sclerosing cholangitis requires a high index of suspicion. The differential diagnoses include primary sclerosing cholangitis, cholangiocarcinoma, and pancreatic cancer. The preoperative diagnosis is likely to be missed due to the lack of specific symptoms; a clinical presentation that may mimic other disorders, especially malignant biliary strictures; and the lack of specific imaging features. This article reports on a 51-year-old man with immunoglobulin G4–associated sclerosing cholangitis without autoimmune pancreatitis. He underwent resection of his extrahepatic bile duct with a hepaticojejunostomy. The diagnosis was confirmed after a histopathological examination. This case highlights the obstacles to making a preoperative diagnosis of immunoglobulin G4–associated sclerosing cholangitis.

Angiosarcoma of the breast is rare and has a poor prognosis due to its aggressive nature. This is a report of two patients with mammary angiosarcomas, each with different clinical presentations, and at either end of the age spectrum. One is an 18-year-old woman who presented with a rapidly enlarging breast mass, and the other a 72-year-old woman whose breast mass was found during screening mammography. The radiological features of mammary angiosarcoma are summarised in this report.

We describe a female adult patient who presented with acute retention of urine and vague abdominal discomfort. A provisional diagnosis of ovarian tumour was made after cross-sectional imaging. At laparotomy a very large retroperitoneal mass was biopsied and found to be a schwannoma after pathological examination. The clinical, radiological, and pathological features of this disease are discussed in this report.