STUDY OF LYMPH NODE CYTOLOGY IN HIV INFECTED PATIENTS

Background and Aim: Human immunodeficiency virus (HIV) infection has become a global pandemic. Persistent generalized lymphadenopathy (PGL) is very common manifestation of HIV infection. Moreover, different opportunistic infections such as tuberculosis (TB) and malignancies may present with lymphadenopathy. This study was performed to evaluate the role of FNAC as a cytological investigative tool in the diagnosis of various lesions in HIV lymphadenopathy. Material and Methods: This study was carried out in Tertiary care Institute of India, over a period of one year. Total 50 cases of HIV lymphadenopathy patients were participated in the study after having signed the Informed Consent Form. Diagnosis of HIV was done by enzyme linked immunosorbant assay (ELISA) test, followed by the CD4 counts by BD FACS Count system in HIV positive patients. FNAC procedure was performed as an OPD procedure in cytology OPD of pathology department. Results: Most common site of HIV lymphadenopathy is cervical lymph node 40 (80%), followed by supraclavicular 6(12%) followed by axillary lymph node 4(8%). The most common lesion found was mycobacterial infection 22(44%), followed by reactive lymphadenitis 15(30%). Non-specific chronic granulomatous lymphadenitis in 10(22%) and 3(6%) cases of acute suppurative lymphadenitis. CD4 count more than 500 cells/ μL was seen in 9 (18%) cases of reactive lymphadenitis and 4 (8%) cases of chronic granulomatous lymphadenitis. Patients with tubercular infection had CD4 count between 200499 cells/ μL in 12 (24%) cases and less than 200 in 10 (20%) cases. Conclusion: FNAC is relatively inexpensive and valuable tool for identification of opportunistic infections, neoplastic lesions and non-neoplastic lesions. It may spare patients lymph node excision and enable immediate treatment of specific infection. This procedure is readily repeatable and can be used for follow up during and after treatment.


Introduction
Acquired immunodeficiency syndrome (AIDS) is known to be caused by a lymphotropic retro-virus ie.Human immunodeficiency virus (HIV), first described by French investigators and later by investigators in United States. AIDS was first recognized in 1981.1 Acquired Immuno Deficiency Syndrome (AIDS) related lymphadenopathy has definite patterns like florid reactive hyperplasia, folliculolysis, explosive follicular hyperplasia, advanced lymphocytic depletion with or without abnormal regressively transformed germinal centers and vascular transformation. HIV disease can be divided on the basis of immunodeficiency into an early stage [cluster of differentiation (CD)4 > 500/μL], an intermediate stage (CD4 = 200-500/μL), and an advanced stage (CD4 < 200/μL).2,3 Most AIDS-defining opportunistic infections and malignancies occur in the advanced stage of the disease. 4,5 HIV enters the body through mucosal tissues and blood and first infects T cells and dentritic cells and macrophages. The infection becomes established in lymphoid tissues, active viral replication is associated with more infection of cells and progression to AIDS. AIDS is a fatal illness that breaks down the body's immunity and leaves the victim vulnerable to life threatening opportunistic infections, neurological disorders or unusual malignancy.6 Lymphoid tissue is a favorite target for the initial viral infection, subsequent opportunist infections and Human Immunodeficiency Virus (HIV) associate neoplasm.7 Persistent generalized lymphadenopathy (PGL) is a very common manifestation of HIV infection. Moreover, different opportunistic infections such as tuberculosis (TB), toxoplasmosis, disseminated fungal infections, atypical mycobacterial infections, Cytomegalovirus infection, and malignancy such as non-Hodgkin lymphoma (NHL) may present with lymphadenopathy.5 TB occurs when the CD4+ count has just started to decline and is 200-500 cells/μL.6,7 Mycobacterium avium complex (MAC) infection is most common with CD4+ count ≤50 cells/μL.8 The role of fine needle aspiration cytology (FNAC) in evaluation of lymphadenopathies is well known. tuberculosis, histoplasmosis, toxoplasmosis and malignant condition such as Kaposi's sarcoma and lymphoma. Fineneedle aspiration cytology (FNAC) offers a simple and effective modality for obtaining a representative sample of the material from lymph nodes, permitting cytological evaluation and other investigations. This study was performed to evaluate the role of FNAC as a cytological investigative tool in the diagnosis of various lesions in HIV lymphadenopathy.

Material and Methods
This study was carried out in Tertiary care Institute of India, over a period of one year. Total 50 cases of HIV lymphadenopathy patients were participated in the study after having signed the Informed Consent Form. Diagnosis of HIV was done by enzyme linked immunosorbant assay (ELISA) test, followed by the CD4 counts by BD FACSCount system in HIV positive patients. FNAC procedure was performed as an OPD procedure in cytology OPD of pathology department. The swelling was localized by careful palpation and site was cleaned with spirit and fixed in favorable position with one hand, and 22 or 23 gauge needle was attached to 10cc syringe fitted on to comeco syringe pistol and FNAC was done. Smears were immediately fixed in 95% ethyl alcohol for PAP staining. Air dried smears were kept for MGG, AFB and special stain for fungi PAS and Methinamine Silver.

Results
Total 50 HIV positive patients were included in this study, out of which 33 are males and 17 are females. This shows that there is predominance of males over the females. Also it is evident that majority of male patients are between 30 to 40 years of age, whereas majority of females are in between 20 to 30 years of age. Most common site of HIV lymphadenopathy is cervical lymph node 40 (80%), followed by supraclavicular 6(12%) followed by axillary lymph node 4(8%). The most common lesion found was mycobacterial infection 22(44%), followed by reactive lymphadenitis 15(30%). Non-specific chronic granulomatous lymphadenitis in 10(22%) and 3(6%) cases of acute suppurative lymphadenitis. The diagnosis of tuberculous lymphadenitis was considered only when smear for Acid Fast Bacilli (AFB) were positive.
Tubercular infection was the most common opportunist infection. These cases were grouped into four categories in which predominant pattern were smears showing caseous necrosis with epithelioid cells in 9 (40.9%) cases. Within this group we found giant cell formation in two cases. Followed by smears showing only caseous necrosis in 8 (36.6%) cases. 3 (13.6%) cases showed only epitheloid cells and 2 (9.09%) cases shows suppurative changes.
CD4 count more than 500 cells/ µL was seen in 9 (18%) cases of reactive lymphadenitis and 4 (8%) cases of chronic granulomatous lymphadenitis. Patients with tubercular infection had CD4 count between 200-499 cells/ µL in 12 (24%) cases and less than 200 in 10 (20%) cases. In chronic granulomatous lymphadenitis 4 (8%) cases had CD4 count more than 500 cells/ µL, 3 (6%) cases had CD4 count in between 200 to 499 cells/ µL and 3 (6%) cases had CD4 count less than 200 cells/ µL. In acute suppurative lymphadenitis 2 (4%) cases had CD4 count in between 200 to 499 cells/ µL, and 1 (2%) case had CD4 count less than 200 cells/ µL.   FNAC is an excellent tool for evaluation of lymphadenopathy in HIV positive patients. FNAC should be performed even when the lymph nodes are less than I em size. Axillary lymph nodes pose problem for the performer of the procedure, but blind FNAC without fixing the node should be attempted as this also provides useful material.
FNAC is useful for detection of mycoses and neoplasia in lymph nodes of HIV infected patients. All suspected neoplasia should be biopsied to avoid false positivity. Infection by Rhodo torula in HIV positive patient is reported for the first time. Association of Kimura's disease and HIV is reported for the first time. CD4, CD8 counts done along with needle aspiration will give better clinicopathological correlation, as immune status vis-a-vis the opportunistic infections in Indian setting can be assessed. Immuno-fluroscence for viral antigens and Toxoplasma, if done, could pick up these infectious agents better on the smears.

Conclusion
FNAC is relatively inexpensive and valuable tool for identification of opportunistic infections, neoplastic lesions and non-neoplastic lesions. It may spare patients lymph node excision and enable immediate treatment of specific infection. This procedure is readily repeatable and can be used for follow up during and after treatment. Correlation of lesions with CD4 T lymphocyte counts provides information about the immune status and stage of the disease. Thus FNAC is a primary, easy and effective diagnostic modality for HIV lymphadenopathy patients. It helps in identifying majority of the reactive and neoplastic lesions and opportunistic infections and guide for the subsequent management of the patient. FNAC findings in the HIV lymphadenopathy are noticeably different in India in comparison to the Western Countries.