Indian Journal of Pathology and Microbiology

LETTER TO EDITOR
Year
: 2012  |  Volume : 55  |  Issue : 1  |  Page : 134--135

Toxoplasma lymphadenitis diagnosed by fine needle aspiration cytology: A rare finding


Monisha Choudhury, Meenu Pujani, Akanksha Jain, Shivali Sehgal 
 Department of Pathology, Lady Hardinge Medical College and associated Hospitals, New Delhi, India

Correspondence Address:
Meenu Pujani
Department of Pathology, Lady Hardinge Medical College and associated hospitals, New Delhi - 110 001
India




How to cite this article:
Choudhury M, Pujani M, Jain A, Sehgal S. Toxoplasma lymphadenitis diagnosed by fine needle aspiration cytology: A rare finding.Indian J Pathol Microbiol 2012;55:134-135


How to cite this URL:
Choudhury M, Pujani M, Jain A, Sehgal S. Toxoplasma lymphadenitis diagnosed by fine needle aspiration cytology: A rare finding. Indian J Pathol Microbiol [serial online] 2012 [cited 2020 Nov 26 ];55:134-135
Available from: https://www.ijpmonline.org/text.asp?2012/55/1/134/94901


Full Text

Sir,

Toxoplasmosis is a zoonotic infection in humans caused by a protozoan intracellular parasite, Toxoplasma gondii. Felines such as cats, serve as definite hosts, while man and other mammals act as intermediate hosts. It affects one-third of the world's population. [1] The majority of toxoplasma cases in immunocompetent hosts are subclinical/asymptomatic, while severe symptomatology including encephalitis, chorioretinitis, pneumonia, myocarditis etc. occur in immunocompromised hosts or congenitally infected newborns. Here, we report a case of a pregnant female with cervical lymphadenopathy diagnosed as toxoplasma lymphadenitis by a combination of fine needle aspiration and serology.

A 21-year-old lady, with 12 weeks pregnancy, presented with a solitary, discrete, painless left lower cervical lymph node measuring 1.5 cm diameter of one month duration. There were no other constitutional symptoms. She is a non-vegetarian, had pulmonary tuberculosis five years back for which she had taken complete course of anti-tubercular treatment.

Fine needle aspiration cytology (FNAC) smears from the cervical lymph node showed the presence of non caseating epithelioid cell granuloma against a polymorphous population of reactive lymphoid cells [Figure 1] and presence of many tissue cysts containing numerous bradyzoites [Figure 2]. These bradyzoites were per-iodic acid Schiff (PAS) positive [Figure 3]. There was no evidence of necrosis, suppuration or giant cell reaction in the background. At this stage, her chest radiograph and computed tomography (CT) scan chest were within normal limits. On serology, enzyme linked immunosorbent assay (ELISA) for IgM anti toxoplasma antibody, IgM anti cytomegalovirus (CMV) antibody and IgG anti rubella anti body was positive. ELISA for IgG anti toxoplasma antibody was negative. However, the patient was soon lost to follow-up.{Figure 1}{Figure 2}{Figure 3}

Toxoplasma gondii, one of the most widely distributed intracellular parasites, exists in three life forms- oocysts, tachyzoites, and bradyzoites (tissue cysts). The oocysts contain sporozoites, and are the product of sexual cycle in the intestine of definitive hosts (felines), which excrete them in their feces. The tachyzoite is the asexual invasive form, which replicates within all nucleated cells. The tissue form/bradyzoite stage can remain dormant in the tissue for decades to be reactivated later.

Toxoplasma infection may be transmitted congenitally or acquired. About one-thirds of the women who acquire infection during pregnancy transmit the infection to fetus and rest give birth to uninfected babies. Early maternal infection (first and second trimester) may result in severe symptomatology and also spontaneous abortion or intrauterine death of fetus, while late maternal infection usually results in a normal fetus. [2] Postnatally, infection can be acquired by ingesting tissue cysts in uncooked or undercooked meat or by ingesting food and water contaminated with oocysts from infected cat feces. Seroprevalence average of Toxoplasma gondii infection in India is 24.3%, a seroconversion rate of 1.5% has been reported. [3] In a study conducted, seroprevalence of 15-33% has been documented in pregnant women in India. [4] Clinically, 80-90% of immunocompetent adults who acquire infection remain asymptomatic with commonest presentation being cervical lymphadenopathy.

The diagnosis of toxoplasmosis is based on a combination of FNAC or tissue biopsy and serological assays detecting antibodies against the parasite. However, if the patient is immunocompromised, serology may be falsely negative. [1] Few case reports of toxoplasma lymphadenitis diagnosed by FNAC (with serology) have been documented in literature. [5],[6]

FNAC classically shows "microgranuloma," which consists of small clusters of characteristic epithelioid histiocytes, with few mature lymphocytes, and show absence of any necrosis, suppuration or giant cells in a background of reactive lymphoid hyperplasia. [6] The organisms may be rarely encountered in aspirate smears. Majority of the cases of toxoplasmosis in pregnancy are asymptomatic and detected by routine anti-toxoplasma antibody screening. Even after extensive data search, to the best of our knowledge, no case of toxoplasma lymphadenitis has been described in a pregnant female, diagnosed by FNAC.

Serological diagnosis of acute infection with toxoplasma can be established by the detection of simultaneous presence of IgG and IgM antibodies to toxoplasma in serum. The presence of circulating IgA antibody favors the diagnosis of acute infection. [2] tests for avidity of IgG antibodies are used to discriminate between recently acquired infection and that obtained in more distant past. Recent studies have illustrated that 35 fold repetitive B1 gene detection by polymerase chain reaction (PCR) amplification of T.gondii DNA is highly sensitive and specific for the diagnosis of toxoplasmosis. [7]

This case is being reported due to the rare presentation of toxoplasmosis as cervical lymphadenopathy in pregnancy, which was diagnosed by demonstration of parasite on cytology, and confirmed by serology, thus confirming the utility of such non invasive, OPD procedure in detecting a potentially lethal infection.

References

1Chen X, Remotti F, Tong GX, Gorczyca E, Hamele Bena D. Fine needle aspiration cytology of subcutaneous toxoplasmosis: A case report. Diagn Cytopathol 2010;38:716-20.
2Ichhpujani RL, Mittal V. Toxoplasmosis- An update. Trop Parasitol 2011;1:9-14.
3Dhumme M, Sengupta C, Kadival G, Rathinaswamy A, Yelumani A. National seroprevalence of Toxoplasma gondii in India. J Parasitol 2007;93:1520-1.
4Khurana S, Bagga R, Aggarwal A, Lyngdoh V, Shiva Priya, Diddi K, et al. Serological screening for antenatal toxoplasma infection in India. Indian J Med Microbiol 2010;28:143-6.
5Pathan SK, Francis IM, Das DK, Mallik MK, Sheikh ZA, Hira PR. Fine needle cytologic diagnosis of toxoplasma lymphadenitis: A case report with detection of toxoplasma bradycyst in a papanicolaou stained smear. Acta Cytol 2003;47:299-303.
6Viguer JM, Heffernan J, Ferrer PL, Peramato G, Vicandi B. Fine needle aspiration of toxoplasma lymphadenitis: A cytohistologic correlation. Acta Cytol 2005;49:139-43.
7Grover CM, Thulliez P, Remington JS, Boothhroyd JD. Rapid prenatal diagnosis of congenital toxoplasma infection by using polymerase chain reaction and amniotic fluid. J Clin Microbiol 1990;28:2297-301.