The remarkable characteristics of the children with colchicine-resistant familial Mediterranean fever in Turkey

OBJECTIVES

Colchicine is the fundamental treatment of familial Mediterranean fever (FMF). Still, 5-10% of patients are not in remission with colchicine treatment. A consensus could not be established for the definition of colchicine resistance in FMF. This study aimed to determine factors that help to predict colchicine resistance in pediatric FMF patients.

METHODS

Patients with FMF that age of diagnosis was under 18 years old were included in our study. Fifty colchicine responsive and 33 colchicine-resistant patients were stratified as groups 1 and 2, respectively. Patients' clinical and laboratory findings were evaluated. Logistic regression analysis was used to determine the risk factors of colchicine-resistant FMF. Receiver operating characteristic (ROC) curve analysis was used to identify and compare the predictive performances of colchicine-resistant FMF models.

RESULTS

Homozygous exon 10 MEFV mutations were frequent in group 2 (Group 1: 34 (68%), group 2: 32 (97%), p = .013). Univariate analysis showed that the age of onset of symptoms, age of diagnosis, chronic arthritis, myalgia and diarrhea during attacks, and the number of attacks, high ISSF and Pras score, high C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) values under colchicine treatment were risk factors for colchicine-resistant FMF. With multivariate analysis, the number of attacks (OR 1.418, CI (95%) 1.149-1.750, p = .001) and high ESR values (OR 1.129, CI (95%) 1.059-1.204, p<.001) were detected as independent risk factors for colchicine-resistant FMF.

CONCLUSION

The predictive factors were determined for pediatric colchicine-resistant FMF in our study. The results will help to early diagnosis and treatment of chronic inflammation in FMF.

Variation of amino acid sequences of serum amyloid a (SAA) and immunohistochemical analysis of amyloid a (AA) in Japanese domestic cats

Amyloid A (AA) amyloidosis, a fatal systemic amyloid disease, occurs secondary to chronic inflammatory conditions in humans. Although persistently elevated serum amyloid A (SAA) levels are required for its pathogenesis, not all individuals with chronic inflammation necessarily develop AA amyloidosis. Furthermore, many diseases in cats are associated with the elevated production of SAA, whereas only a small number actually develop AA amyloidosis. We hypothesized that a genetic mutation in the SAA gene may strongly contribute to the pathogenesis of feline AA amyloidosis. In the present study, genomic DNA from four Japanese domestic cats (JDCs) with AA amyloidosis and from five without amyloidosis was analyzed using polymerase chain reaction (PCR) amplification and direct sequencing. We identified the novel variation combination of 45R-51A in the deduced amino acid sequences of four JDCs with amyloidosis and five without. However, there was no relationship between amino acid variations and the distribution of AA amyloid deposits, indicating that differences in SAA sequences do not contribute to the pathogenesis of AA amyloidosis. Immunohistochemical analysis using antisera against the three different parts of the feline SAA protein—i.e., the N-terminal, central, and C-terminal regions—revealed that feline AA contained the C-terminus, unlike human AA. These results indicate that the cleavage and degradation of the C-terminus are not essential for amyloid fibril formation in JDCs.

A case of a ten-year old girl with dominantly inherited Familial Mediterranean fever in Republic of Macedonia

The Familial Mediterranean fever (FMF, MIM249100) is an autoimflammatory genetic disease characterized with recurrent painful attacks in the abdomen, chest or joints, usually accompanied with high body temperature. It is classically inherited in an autosomal recessive manner. It is associated with mutations of the MEFV gene, coding for the protein pyrin. More than 140 mutations of the MEFV gene are defined worldwide. Despite the progress in establishing reliable tests practical for routine use, as much as 20% of the patients with FMF remain without a detectable mutation in the MEFV gene. This is the main reason why the diagnosis of FMF remains still a clinical one, according to Tel Hashomer criteria. A 10-year old girl admitted to the Clinic of Pediatrics at the Faculty of Medicine in Skopje for unexplained fever. After numerous laboratory analyses and specialist consultations were done, genetic testing for FMF was requested. The presence of an heterozygous mutation E148Q was confirmed at the Institute for Immunobiology and Human Genetics using a PCR based, reverse hybridization method. Administration of colchicine, the therapy of choice, in a dose of 1.5 mg/day, lead to complete resolution of the symptoms within some days following commencement. Although the disease is classically inherited in a recessive manner, some atypical cases of autosomal dominant inheritance are described. Our patient may be another example supporting the unusual dominant inheritance, since the heterozygous state for the E148Q mutation was the only positive finding in the genotyping of the 12 most frequent MEFV mutations.

Familial Mediterranean fever with onset at 66 years of age

The patient was a 68-year-old woman who had experienced recurrent febrile episodes since 66 years of age. Despite various examinations and treatments, the etiology remained unclear. Further examinations following another referral failed to uncover the cause. Therefore, despite her age, it was presumed that she had familial Mediterranean fever. An analysis of the familial Mediterranean fever (MEFV) gene detected heterozygous L110P, E148Q, and R202Q mutations. No further febrile episodes occurred after colchicine treatment was initiated. Familial Mediterranean fever presenting in patients in their sixties is extremely rare.

Expression of ASC in renal tissues of familial mediterranean fever patients with amyloidosis: postulating a role for ASC in AA type amyloid deposition

Familial Mediterranean fever (FMF) is characterized by recurrent attacks of fever and serositis; in some cases, ensuing amyloidosis results in kidney damage. Treatment with colchicine reduces the frequency and severity of FMF attacks and prevents amyloidosis, although the mechanisms behind these effects are unknown. Pyrin, the protein product of the MEFV gene, interacts with ASC, a key molecule in apoptotic and inflammatory processes. ASC forms intracellular speck-like aggregates that presage cell death. Here we show that cell death after ASC speck formation is much slower in nonmyeloid cells than in myeloid cells. Additionally, we demonstrate that colchicine prevents speck formation and show that specks can survive in the extracellular space after cell death. Because we also found that ASC is expressed in renal glomeruli of patients with FMF but not in those of control patients, we posit that high local ASC expression may result in speck formation and that specks from dying cells may persist in the extracellular space where they have the potential (perhaps in association with pyrin) to nucleate amyloid. The fact that speck formation requires an intact microtubule network as shown here could potentially account for the ability of prophylactic colchicine to prevent or reverse amyloidosis in patients with FMF.

Colchicine use in children and adolescents with familial Mediterranean fever: literature review and consensus statement

The daily application of colchicine is the standard therapy for prophylaxis of attacks and amyloid deposition in familial Mediterranean fever. However, because of many issues (eg, dosage, time of introduction, etc), no standardized treatment recommendations have been established. In this work we review the available literature on colchicine use with respect to its indication, efficacy, mode of application, and safety in children and adolescents with familial Mediterranean fever. On the basis of this analysis, a consensus statement on the application of colchicine in children and adolescents with familial Mediterranean fever was developed by caregivers from Germany, Austria, and Turkey.