Evaluation of the percentage effectiveness of immatur granulocyte in determining the attack status in patients diagnosed of family mediterranean fever

Aim/Backround: Familial Mediterranean Fever (FMF) is inherited autosomal recessively; exotically with episodes of peritonitis, pleuritis, arthritis (serositis) and recurrent fever. It is mostly seen in individuals of Turkish, Armenian, Arab and Jewish origin around the Mediterranean region. It is caused by mutations in the MEFV gene, which encodes the AAA pyrin protein. The complications that most affect the prognosis are the development of amyloidosis and renal involvement. Immature granulocytes are the common name of granulocyte precursors found in the bone marrow, which are not found in peripheral blood except in the neonatal period. With routine hemogram analysis, IG number and IG percentage are obtained in a short time, repeatable, does not require additional blood, additional time. It is useful in the early diagnosis of inflammation and in excluding inflammation. Our study included 96 patients with a diagnosis of FMF and 68 healthy children aged between 1 month and 17 years, who applied to the Tokat Gaziosmanpaşa University Faculty of Medicine, Pediatrics Outpatient Clinic and Pediatric Emergency Department with a FMF attack. We aimed to compare subclinical/clinical inflammation markers such as NLR(absolute neutrophil count/absolute lymphocyte count), TLR (absolute platelet count/absolute lymphocyte count), MPV, and SII (absolute neutrophil count X platelet count/absolute lymphocyte count), which were measured in the attack and non-attack periods, with the control group to compare the percentages of immature granulocytes (IG %) in the attack period with other infection markers and to evaluate the effectiveness of IG % in determining the attack period. Materials and Methods: 96 patients aged 1 month to 17 years a diagnosis of FMF who applied to Tokat Gaziosmanpaşa University Faculty of Medicine Pediatrics Polyclinic and Pediatric Emergency between 01/06/2022 -30/01/2023 were included in the study. Hemogram, Sedim, CRP, SAA tests were taken from the patients participating in the study during the attack period and at least 2 weeks after the attack. NLR, TLR, SII values were calculated from the parameters that could be measured in the hemogram. The number of IG, IG %, NLR, TLO, and SII values in the examinations taken during the attack period were compared with the post-attack period. In the control group, 68 patients without infection and chronic disease were included in the study retrospectively. NLR, TLR, SII and IG numbers from the control group were compared with FMF patients in the attack and non-attack phase. Results: NLR ,TLR value was found to be statistically significantly higher during the attack period when compared to the period between attacks (p<0.001); No significant difference was found between the non-attack period and the control group (p=0.321, p=0.277); during the attack, it was significantly higher when compared to the control group (p<0.001). SII was found to be significantly higher in the attack period compared to FMF patients in the attack and attack-free period (p<0.001); there was no significant difference between the patients in the healthy control group and the patients in the period between attacks (p=0.434). During the attack, it was significantly higher when compared to the control group (p<0.001). In our study, while the IG % and IGS measured during the attack period were statistically significant compared to the post-attack period (p<0.001), no significant difference was found between the non-attack and control groups (p= 0.581, 0.446, respectively), ıt was also significantly higher during the attack when compared to the control group (p<0.001) As a result of ROC analysis, the cut-off value of IG % was found to be 0.3 to predict FMF attack. (81.3% sensitivity, 85.4% specificity). The area under the curve (AUC) of the percentage of IG to estimate the probability of having an attack in FMF patients was 0.891 (0.844-0.938) with a 95% confidence interval (CI) (p<0.001). Conclusion: NLR, TLR, and SII can be important markers of systemic inflammation that can be used frequently in FMF patients because they are inexpensive, readily available, and easily calculated. Since there is no significant difference between relapse-free patients and control groups, it may not be appropriate to use NLR, TLO, and SII as subclinical inflammation markers. In our study, IG % and IGS measured during the attack period were found to be statistically significant compared to the post-attack period (p<0.001); As a result of ROC analysis, the cut-off value of IG % was found to be 0.3 to predict FMF attack. (81.3% sensitivity, 85.4% specificity) The area under the curve (AUC) of the percent IG to predict the probability of having an attack in FMF patients was 0.891 with a 95% confidence interval (CI) (p<0.001). This made us think that IG % is a useful parameter in predicting the diagnosis of relapse. KEYWORDS: Familial Mediterranean Fever, child, amyloidosis, immatur granulocyte