[Tuberculosis caused by Mycobacterium africanum]. / Tuberkulose forårsaget af Mycobacterium africanum.

Tuberculosis (TB) is caused by pathogenic species within the Mycobacterium tuberculosis complex (MTBC). In the present case, a 40-year-old African man was admitted acutely. Despite negative microscopy, anti-TB treatment was initialized. Thirteen hours after hospitalisation, the patient suffered circulatory failure and died. Post mortem material from the lungs and pericardia tested positive for MTBC and was identified as Mycobacterium africanum by a new molecular method that enables identification of six of the eight MTBC species and provides clinicians with species-specific results.

Line probe assay for differentiation within Mycobacterium tuberculosis complex. Evaluation on clinical specimens and isolates including Mycobacterium pinnipedii.

A line probe assay (GenoType MTBC) was evaluated for species differentiation within the Mycobacterium tuberculosis complex (MTBC). We included 387 MTBC isolates, 43 IS6110 low-copy MTBC isolates, 28 clinical specimens with varying microscopy grade, and 30 isolates of non-tuberculous mycobacteria. The assay was 100% specific and identified all 387 isolates and 98% of all IS6110 low-copy strains in concordance with the gold standard. The 2% discrepancy was caused by 1 isolate showing a faint restriction fragment length polymorphism (RFLP) pattern. The assay could provide specifies identification in 13 of 19 (68%) microscopy-positive specimens and 0 of 9 microscopy-negative specimens. To our surprise, the probe for M. africanum subtype I reacted with M. pinnipedii. This cross-reaction has not previously been reported. The assay was rapid, easy to perform and directly applicable in highly smear-positive specimens. We predict that the assay will enable enhanced surveillance of species-specific treatment outcome, which may change treatment regimens.