The cytology of HIV-induced immunosuppression. Changing pattern of disease in the era of highly active antiretroviral therapy

Review of HIV-Related Cytopathology

Exfoliative and aspiration cytologies play a major role in the management of patients with human immunodeficiency virus infection. Common cytology samples include cervicovaginal and anal Papanicolaou tests, fine needle aspirations, respiratory specimens, body fluids, Tzanck preparations, and touch preparations from brain specimens. While the cytopathologists need to be aware of specific infections and neoplasms likely to be encountered in this setting, they should be aware of the current shift in the pattern of human immunodeficiency virus-related diseases, as human immunodeficiency virus patients are living longer with highly active antiretroviral therapy and suffering fewer opportunistic infections with better antimicrobial prophylaxis. There is a rise in nonhuman immunodeficiency virus-defining cancers (e.g., anal cancer, Hodgkin's lymphoma) and entities (e.g., gynecomastia) from drug-related side effects. Given that fine needle aspiration is a valuable, noninvasive, and cost-effective tool, it is frequently employed in the evaluation and diagnosis of human immunodeficiency virus-related diseases. Anal Papanicolaou tests are also increasing as a result of enhanced screening of human immunodeficiency virus-positive patients for cancer. This paper covers the broad spectrum of disease entities likely to be encountered with human immunodeficiency virus-related cytopathology.

Combining fine-needle aspiration biopsy (FNAB) and high-resolution melt analysis to reduce diagnostic delay in Mycobacterial lymphadenitis

Tuberculous lymphadenitis is the most common cause of extra-pulmonary tuberculosis (TB) in developing countries. Lymphadenitis caused by non-tuberculous mycobacteria (NTM) requires consideration, particularly in immunocompromised patients and children in developed countries. Fine-Needle Aspiration Biopsy (FNAB) offers a valuable specimen collection technique, but culture confirmation, mycobacterial speciation and drug resistance testing (if indicated) is often unavailable in TB endemic areas and result in unacceptable diagnostic delay. We evaluated the diagnostic value of high-resolution DNA melting (HRM) analysis in the diagnosis of mycobacterial lymphadenopathy using FNAB and an inexpensive transport medium. Specimens were collected from patients referred to the FNAB Clinic at Tygerberg Hospital (June 2007-May 2008) with clinical mycobacterial lymphadenitis. Cytology, culture, and HRM were performed on all specimens. The reference standard for disease was defined as positive cytology (morphological evidence plus mycobacterial visualization) and/or a positive culture. Specimens were collected from 104 patients and mycobacterial disease was confirmed in 54 (51.9%); 52 Mycobacterium tuberculosis, 1 Mycobacterium Bovis BCG and 1 NTM. Cytology was positive in 83.3% (45/54) and culture in 72.2% (39/54) of patients. HRM identified 57.4% (31/54) of cases. By using the defined reference standard, we recorded 94.0% specificity and 51.9% sensitivity (positive predictive value 90.3%) with HRM analysis.HRM analysis allowed rapid and species specific diagnosis of mycobacterial lymph adenitis in the majority of patients, permitting early institution of appropriate therapy. Optimization of this technique requires further study.

Diagnostic yield of fine-needle aspiration cytology in HIV-infected patients with lymphadenopathy in the era of highly active antiretroviral therapy

Fine-needle aspiration (FNA) cytology has an established role in the investigation of lymphadenopathy in HIV-infected patients. However, changes in the spectrum of disease have been observed since the introduction of highly active antiretroviral therapy (HAART). The aim of the study was to establish whether FNA cytology remains a useful investigative tool in the post-HAART era and to determine whether the cytology results reflect the changing patterns of disease. Retrospective search of the cytopathology database at University College London Hospitals identified 73 FNA cytology procedures performed in 62 patients between January 1998 and December 2006. FNA cytology showed significant disease in 90% of adequate samples. The most common diagnoses were persistent generalized lymphadenopathy (PGL, 50%), infection (22%) and malignancy (18%). Diagnoses could not be made in 31 % of patients because of inadequate sampling. An open lymph node biopsy was subsequently performed in 27% of patients. FNA cytology remains an important initial investigation in the post-HAART era, particularly in the diagnosis of PGL, infection and malignancy. Difficulties in diagnosis of Castleman disease and Hodgkin's lymphoma by FNA cytology are recognized.

Diagnosing mycobacterial lymphadenitis in children using fine needle aspiration biopsy: cytomorphology, ZN staining and autofluorescence -- making more of less

Although the incidence of TB has stabilized or declined in most world regions, it is increasing in Africa, Southeast Asia, and the Eastern Mediterranean, fuelled by the HIV pandemic. More than 4,000 people died daily from TB-related illnesses in 2005. TB is a major cause of childhood morbidity and mortality in these developing countries, and there is an urgent need for rapid and definitive modalities for mycobacterial diagnosis in children. This prospective study in Tygerberg Hospital, Cape Town, South Africa, evaluates the ability of fine needle aspiration biopsy (FNAB) to diagnose mycobacterial lymphadenitis in children, using cytomorphology, autofluorescence on Papanicolaou stained smears, Ziehl-Nielsen (ZN) staining and/or culture. FNABs were performed on 200 children, and 25 (12.5%) aspirates were inadequate. Cultures were positive in 79/175 (45%); Mycobacterium tuberculosis was identified in 61 and Mycobacterium bovis BCG in 18 cases. Using culture as the gold standard, the concordance of the different techniques was as follows: cytomorphology 70%, ZN staining 73%, and autofluorescence 68%. Using an alternative gold standard (culture positive and/or suggestive cytomorphology plus positive autofluorescence or ZN smear), the "true" diagnostic performance of the various techniques was as follows: cytomorphology-sensitivity 78%, specificity 91%, positive predictive value (PPV) 93%, ZN staining - sensitivity 62%%, specificity 97%, PPV 97%; autofluorescence-sensitivity 67%, specificity 97%, PPV 97%; and culture-sensitivity 75%, specificity 100%, and PPV 100%. FNAB was shown to provide a rapid and definitive diagnosis in the majority of cases of suspected tuberculous lymphadenitis in children, based on cytomorphology and identification of the organism.

Mycobacterial autofluorescence in Papanicolaou-stained lymph node aspirates: a glimmer in the dark?

This study was undertaken to determine the value of incorporating fluorescence into cytopathological evaluation of lymph node fine-needle aspiration (FNA) specimens suspected of harboring mycobacterial species. The study population consisted of 1,044 HIV-positive and -negative patients referred for FNA to the cytopathology unit of a South African medical school located in a very high HIV prevalence region. Each aspirate was assessed on routine Papanicolaou-stained slides for morphologic characteristics of mycobacterial infection. The same glass slides were then viewed under fluorescent microscopy to determine the presence or absence of mycobacterial autofluorescence. Using multivariate analysis, results of both cytology and fluorescence were compared with mycobacterial culture as the final arbiter of the presence of organisms. In this large clinical study, compared with culture, cytomorphology showed sensitivity of 84.9%, but low specificity of only 50.9%. Fluorescence demonstrated lower sensitivity of 65.9%, but improved specificity of 73.0%. Taken together, positivity of both cytology and fluorescence improved specificity to 81.8%. Fluorescent microscopy is rapid, inexpensive, and cost-effective; neither radioactive materials nor further staining are required. It is felt that this methodology would be of diagnostic benefit if used on morphologically suspicious samples in areas with a high prevalence of HIV and mycobacterial infections. Appropriate therapy could be commenced within hours of FNA, with reduction in the current number of patients lost to follow-up while awaiting results of culture. The technique is readily extended to other FNA types such as deep organ aspirates. Autofluorescence of organisms specifically requires usage of Papanicolaou staining; the technique cannot be used in histopathologic specimens stained with hematoxylin-eosin.

Infarction of acinic cell carcinoma in a patient infected with HIV: a complication of fine-needle aspiration cytology obscuring definitive diagnosis

Infarction of salivary gland tumors has been reported following fine-needle aspiration cytology (FNAC) and, rarely, as a spontaneous event. Patients infected with the human immunodeficiency virus (HIV) often have salivary gland lesions and FNAC plays a role in the preliminary investigation of such swellings. We report a case of a parotid swelling in a patient infected with HIV where infarction of acinic cell carcinoma following FNAC lead to difficulty in cytological evaluation of the subsequent aspirate.