[Diagnostic value of occult haemolacria]

To study tears for occult (latent) haemolacria in women and compare the representativeness of the main methods of tear examination.

Tear samples from 72 women aged between 18 and 46 years were evaluated using two methods: microscopic and chemical with reagent test strips.

In the follicular phase of the menstrual cycle, erythrocytes in tears were detected in 59.1% (13) subjects, which was significantly higher (χ²=4.2, p=0.041) compared to the luteal phase - erythrocytes were detected in 40.9% (9) women. The proportion of women in the luteal phase of the cycle who had single epithelial cells in the tear (76.9%) was significantly lower (χ²=5.2, p=0.022) than in women in the follicular phase (83.9%). The predictive value of the chemical method was 0.53 of that of the microscopic one. Microscopically, blood was detected in 30.6% of tear samples, while chemically - in 16.7%. An associative relationship was found between occult haemolacria in women and a diagnosis of endometriosis (K=0.75, p≤0.05). The proportion of women with erythrocytes in tears determined with the chemical method was 41.7% in patients with endometriosis, which was significantly higher (χ²=6.5, p=0.011) than 11.7% in women without endometriosis.

Fluctuations of hormones during the menstrual cycle are reflected in tear composition, manifested as an increase in the number of epithelial cells in the luteal phase, and erythrocytes in the follicular phase. Erythrocytes found in a tear amid accumulations of epithelial cells, their glandular atypia and neutrophilic infiltration in patients with endometriosis may indicate the manifestation of extragenital endometriosis. The microscopic method turned out to be more sensitive in detecting occult haemolacria, and additionally it provided information about other cells. At the same time, the chemical method, which was relatively diagnostically informative, faster and technically simpler, can be used for screening.