Evaluation of the relationship between serum amiloid a and urine heat-shock protein (HSP70) levels in familial mediterranean fever (FMF) patients

Introduction and Objective: Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disease characterized by recurrent attacks of fever, peritonitis, pleuritis, pericardial inflammation and arthritis. HSP70, which is one of the heat shock proteins (HSP), is a group of proteins whose levels increase in relation to stress factors such as inflammation, infection and tissue damage. In our study; It was aimed to evaluate the relationship between Serum Amyloid A (SAA) level and urinary heat-shock protein (HSP70) levels in Familial Mediterranean Fever (FMF) patients and to investigate whether urinary HSP70 level can be used instead of SAA as a non-invasive test in the follow-up of chronic subclinical inflammation without exacerbation. Materials and Methods: A total of 119 patients under the age of 18, who were followed up with the diagnosis of FMF in the Pediatric Rheumatology Outpatient Clinic of Istanbul University, Istanbul Medical Faculty and 47 healthy controls were included in the study. 91 of the patients had normal SAA levels and 28 of them had high SAA levels, when the files of FMF patients were examined. Urine samples were taken from the patient and control groups and HSP70 was studied in the urine. Demographic information and laboratory results of the patient and control groups were obtained through the hospital automation system, patient files and patient interviews. Results: The patient group with normal SAA levels consisted of 47 women (51.6%), 44 men (48.4%) and their mean age was 12.2±3.8 years. 17 women (60.7%) and 11 men (39.3%) of the patient group with high SAA levels had a mean age of 13.6±3.8 years. The healthy control group consisted of 16 women (34%), 31 men (66%) and their mean age was 8.8±4.0 years. There was no statistically significant difference between the patient and control groups in terms of gender and age distribution (p>0.05). M694V mutation was positive in 70 of 119 patients (58.8%).12 patients (13.2%) with normal SAA levels and 12 patients (42.9%) with high SAA levels were found to be M694V homozygous. When the drug use status of the patients was examined, the rate of colicin resistance (anti-IL-1, anti-IL-6 or anti-TNF-alpha use) was found to be significantly higher in the group with high SAA level than in the group with normal SAA (p < 0.05). There was no significant difference between urine HSP70 values in the control group, the group with normal SAA and high SAA level (p=0.228). Conclusion: In our study, no significant difference was found between the urine HSP70 values of patients with normal SAA levels, patients with high SAA levels, and the control group. Our study is the first to investigate the relationship between SAA level and urine HSP70 level in FMF patients. Key Words: Familial Mediterranean Fever, Serum Amyloid A, SAA, heat shock protein, HSP70