Endoscopic ultrasound guided fine needle aspiration allows accurate diagnosis of mycobacterial disease in HIV-positive patients with abdominal lymphadenopathy

Background: Abdominal lymphadenopathy in HIV remains a challenge due to inaccessibility of lymph nodes and multitude of causes. The diagnostic yield of EUS FNA in HIV-infected patients with abdominal lymphadenopathy in the setting of high tuberculosis (TB) prevalence was assessed. Methods: Prospective cohort study was conducted in tertiary referral centres recruiting symptomatic HIV+ patients (N=31, mean age 38.5 years, mean CD4 count 124 cells/μl, WHO stage 3-4 with abdominal lymphadenopathy. EUS was performed to assess lymph node characteristics and FNA aspirate subjected to cytological analysis, microbial culture and PCR. Results: EUS appearance of lymph nodes was highly variable. Mycobacterial infections were the most common cause of lymphadenopathy in this cohort. Of the 31 patients 21/31 67.7 % had mycobacterial infections; 17 (80.9 %) of these were tuberculosis. Cytology failed to identify 23.8% and culture 38.1% of cases. PCR identified 16/17 (94.1%) of these cases. EUS-FNA altered the management of more than half of the patients. Conclusions: Mycobacterial disease was the commonest cause of lymphadenopathy in HIV but a third of patients had reactive lymphadenopathy. By combining the appearance of EUS FNA and cytological aspirate we could develop a diagnostic algorithm with a high PPV and NPV to identify patients in whom further analysis with PCR would be useful. PCR was highly accurate in confirming mycobacterial disease and determining genotypic drug resistance.