Toxoplasma Lymphadenopathy: A Comparative Diagnostic Assessment of Clinical, Serological and Histopathological Findings

Introduction: Toxoplasma Gondii (TG) is a zoonotic protozoan with extensive symptomatology. Toxoplasmic lymphadenopathy is considered an affirmative sign and is proved by a biopsy of the enlarged nodule. This study was conducted to compare the clinical, serological, and histopathological findings for the diagnosis of toxoplasmic lymphadenopathy.  Materials and Methods: This study involved biopsy examinations from twelve cases with TG lymphadenopathy. ELISA serological tests were performed for TG specific IgM and IgG immunoglobulins. PCR was done to ratify the results obtained by ELISA.  Results: The ages of the patients ranged from ۱۵ to ۴۸ years (mean=۲۷.۸). Most of the cases are male n=۸(۶۶.۷%), while female n=۴(۳۳.۳%). The asthenia was not only the most frequent clinical presentation (۸۳.۳%), but it also last longer. All cases had a positive biopsy. Eight (۶۷.۷%) cases revealed seropositivity. Two of them had positive PCR in those who were positive IgM, suggesting that the infection was acute. Six (۵۰%) cases revealed positive IgG tests, while those with negative serology were ۴(۳۳.۳%). The site of lymph nodes involvement had been assessed and mostly cervical (۹۱.۶%).  Conclusion: The histopathological results yielded ۱۰۰% positive findings, thus biopsy was very important in the diagnosis and differential diagnosis of lymph nodes enlargement. The chronic phase of toxoplasmosis does not show the protozoa in the blood causing an absent DNA band for amplification of the PCR cycles, which could explain the lack of bands particular for TG. A negative serological test does not exclude toxoplasmic lymphadenitis, especially in immune-compromised patients.

Keywords:

Biopsy , ELISA , Toxoplasma gondii , Lymphadenopathy , Real-time PCR , Serology , Lymph node