DIAGNOSIS OF TUBERCULOUS LYMPHADENITIS IN AN AREA OF HIV-INFECTION AND LIMITED DIAGNOSTIC

In order to evaluate procedures leading to the diagnosis of tuberculou s lymphadenitis, a prospective clinical study was carried out of patie nts with lymphadenopathy admitted to the medical wards of a referral h ospital in Tanzania. The yield of diagnostic procedures (direct aurami ne/Ziehl-Neelsen (ZN) stained smears, Lowenstein-Jensen (LJ) cultures, cytology and histological examinations of fine needle aspirations (FN A) and biopsy material of lymph nodes, respectively, was compared, We also tried to identify clinical diagnostic markers. One hundred and tw enty eight (99 HIV-seropositive) patients were included, In 89 (67 HIV -positive) patients TB lymphadenitis could be proven, Histology and LJ culture of a lymph node biopsy had the highest diagnostic yield, 85% and 88% respectively, followed by detection of acid fast bacilli (AFB) in biopsy smear (53%) and in fine-needle aspirations 35%). The diagno stic yield of the several procedures was not affected by associated HI V infection. Macroscopic caseation was 100% predictive for TB with a s ensitivity of 69%. Firm and matted lymph nodes, ESR >100 mm/hr, a posi tive PPD skin test and pleural opacity on a chest x-ray proved to be i ndependent predictors for TB. Retrospective testing of a stepwise diag nostic approach based on direct smears of FNA, macroscopic visible cas eation and direct smear of biopsy tissue, suggests that in 93% of the patients a definite diagnosis of TB lymphadenitis could have been made . Our data suggest that in HIV/TB epidemic areas most of the cases of TB lymphadenitis can be diagnosed correctly by simple and cheap method s which are generally available at district hospitals. Our findings ne ed further prospective validation, however.