A man with a blistering eruption and tuberculosisBMJ 2012; 344 doi: https://doi.org/10.1136/bmj.d8351 (Published 06 January 2012) Cite this as: BMJ 2012;344:d8351
- Chi-Ho Lee, resident1,
- Michele M A Yuen, resident1,
- Wing-Sun Chow, associate consultant1,
- Annette W K Tso, assistant professor2,
- Chi-Keung Yeung, associate consultant1,
- Johnny C Y Chan, resident1,
- Chi-Hung Chau, associate consultant3,
- Karen S L Lam, chair professor12
- 1Department of Medicine, Queen Mary Hospital, Pokfulam, Hong Kong
- 2Department of Medicine, University of Hong Kong, Hong Kong
- 3Grantham Hospital, Wong Chuk Hang, Hong Kong
- Correspondence to: C-H Lee
A 59 year old Chinese man was admitted for a blistering eruption. He had stopped using injected drugs and drinking alcohol three years ago after having previously drunk two cans of beer, equivalent to 2-3 units of alcohol, a week. Two years ago, he had been diagnosed with chronic hepatitis C virus (HCV) infection and had recently been diagnosed with pulmonary tuberculosis, for which he was started on isoniazid 600 mg, rifampicin 600 mg, ethambutol 1.5 g, and pyrazinamide 2 g three times a week.
Three days after starting this treatment, he developed a progressive blistering eruption over his neck and both upper limbs, which affected his lateral arms and forearms but spared the oral mucosa and other parts of his body. Nikolsky’s sign was negative. He stopped all the drugs two weeks later because of a suspected drug eruption.
He had a normal blood cell count with a haemoglobin of 120 g/L (reference range 124-168). Liver enzymes were raised, with alanine aminotransferase at 65 U/L (7-36), aspartate aminotransferase at 96 U/L (14-30), alkaline phosphatase at 158 U/L (32-93), and γ-glutamyl transferase at 648 U/L (11-62), as was total bilirubin at 63 µmol/L (14-23). Liver ultrasound was normal and his serum α fetoprotein was 2 ng/ml (<4).
No antibodies against intercellular substances and dermoepidermal junction antigens were found in his blood. A skin biopsy of a blister on his forearm showed subepidermal bullae, but immunofluorescence for hemidesmosomal protein at the dermoepidermal junction was negative.
1 What are the differential diagnoses?
2 What further investigations are needed to confirm the diagnosis?
3 What risk factors …