Correlation of Rk39-Specific Antibodies and Thyroid Function in Patients with Visceral Leishmaniasis

This study aimed to determine whether anti-rK39 antibodies were diagnostic markers for visceral leishmaniasis (kala-azar) and to evaluate the correlation between age and gender in disease occurrence in Iraqi patients. In addition, it aimed to evaluate the correlation between thyroid hormones, i.e., thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4) and anti-rK39 antibodies.

Immunochromatographic technique used for anti-rK39 antibodies detection. Enzyme-linked immunosorbent assay was used for determining the serum TSH, T3, and T4 levels.

One hundred thirty-eight patients with visceral leishmaniasis were included. The mean age was 27.65±11.60 years. Sixty-one patients (44.2%) were males, and their mean age was 29.65±11.10 years. The mean age of females was 26.12±11.89 years. Anti-rK39 antibodies were detected in 11.59% of patients. Anti-rK39 antibodies were equally detected (5.8%) in both genders without a significant difference (p=0.212) or correlation between gender and anti-rK39 antibodies (p=0.623). There was neither a significant difference (p>0.05) nor correlation between gender; age groups according to gender and anti-rK39 antibodies (p>0.05). Both males and females who were positive for anti-rK39 antibodies had normal TSH, T3, and T4 levels. Only one patient who was positive for anti-rK39 antibodies had an elevated T4 level (>12 μg/dL). Neither a significant difference nor correlation was reported among genders; anti-rK39 antibody positivity (p>0.05); and TSH, T3, and T4 levels.

Anti-rK39 antibodies, a daignostic marker for visceral leishmaniasis have no correlation with patients age and gender. Serum TSH and T3 levels were not affected by visceral leishmaniasis. Visceral leishmaniasis causes the increase in serum T4 levels. Thyroid involvement appears to be uncommon in patients who present with visceral leishmaniasis.