AFB
Fish tank/swimming pool granuloma
Due to Mycobacterium marinum, which causes a localised papular or
nodular skin lesion, usually in people who clean aquaria or swimming
pools. Diagnosis is by biopsy and culture (acid-fast bacilli).
Treatment: single lesion excision (may suffice). May need antibiotic
therapy e.g. clarithromycin (o) bd for 3–4 months plus rifampicin for
severe or unresponsive infection. Seek expert advice.