TEAR AND SALIVA FERNING TESTS IN SJOGRENS-SYNDROME (SS)

The purpose of this study was to evaluate the tear ferning test (TFT) and the saliva ferning test (SFT) as diagnostic tests for xerophthalmi a and xerostomia respectively in patients with SS. Dried samples of fr eshly produced tears and saliva from: (A) 36 healthy controls without sicca symptoms, (B) 61 patients with primary SS, (C) 53 patients with secondary SS and (D) 22 patients with psychiatric disorders receiving antidepressants, were examined by polarizing light microscopy. All ind ividuals included in the study were postmenopausal women. The crystall ization was classified into 4 types according to the ferning phenomeno n: uniformity, branching, spreading and integrity (type I normal and I I, III, TV abnormal). Abnormal TFT was found in tear samples of: (A) 8 /72 normal control eyes, (B) 110/122 prim SS eyes, (C) 86/106 sec SS e yes and (D) 30/44 psychiatric patients' eyes. Abnormal SFT was found i n: (A) 6/36 of normal controls, (B) 59/61 of prim SS, (C) 51/53 of sec SS patients and (D) 16/22 of psychiatric patients. The differences of both TFT and SFT of patients with prim SS and sec SS versus controls were significant (p < 0.001). The sensitivity of TFT was found to be h igh both in prim SS (90%) and in sec SS (81%). In addition the specifi cities of TFT and SFT were high 89% and 83% respectively. On the other hand the differences of TFT and SFT in psychiatric patients receiving antidepressants versus normal controls were also significant (p < 0.0 5 and p < 0.025 respectively). According to our data TFT and SFT are s imple, sensitive and specific tests to evaluate xerophthalmia and xero stomia in SS and probably in other conditions characterized by mucous membrane dryness.