Cryptococcal lymphadenitis diagnosed by fine needle aspiration cytology: a review of 15 cases.

Objective: To review the cases of cryptococcal infection presenting primarily with lymphadenopathy and diagnosed on fine needle aspiration cytology (FNAC) and to evaluate the various cellular reactions in this infection.

Study Design: Retrospective review of 15 cases of cryptococcal lymphadenitis diagnosed on FNAC between 1999 and 2007.

Results: A total of 15 cases of cryptococcal lymphadenitis were diagnosed, out of which 10 occurred in a setting of immunosuppression, and in 5 cases there was no obvious immunocompromised clinical setting. Eight patients had human immunodeficiency virus infection, and 2 were post-renal transplant. These patients presented with lymphadenopathy at various sites, with size ranging from 0.5 to 3 cm. The aspirate in most of the cases was fluid material. Detailed cytologic examination of the smears revealed a predominantly chronic inflammatory infiltrate and showed the presence of numerous organisms of varying size present both intracellularly as well as extracellularly. The 2 patients with renal transplant had a low load of organisms. Three cases showed well-formed granulomas, and a giant cell reaction was seen in 9 cases. The periodic acid-Schiff/Alcian blue stain was applied in all cases and confirmed the mucopolysaccharide capsule. One case represented dual infection with Mycobacterium tuberculosis and Cryptococcus. Unlike other fungal infections, the granulomatous reaction and associated inflammatory response in cryptococcal infection is very slight or absent.

Conclusion: FNAC can expedite an accurate diagnosis of cryptococcal lymphadenitis, which helps in the prompt initiation of treatment. The cellular response and the organism load are variable.