Israel Medical Association Journal

Background: Familial Mediterranean fever (FMF) is a recessively inherited disease with a variety of clinical presentations. The disease is associated with mutations in the FMF gene (MEFV), which encodes for the pyrin protein. The role of the E148Q pyrin mutation in the FMF phenotype remains inconclusive, and some authors even view it as a disease-insignificant polymorphism. The calculated change, imposed by this mutation on pyrin structure, may help to understand the role of this mutation

Objectives: To calculate the relative electrochemical effect of the E148Q mutation on the structure of pyrin protein.

Methods: The electronic properties of the wild-type pyrin molecule and its common mutated forms were computed for the full-length molecule and its segments, encoded by exons 2 and 10, using the HyperChem 7.5 program with one of the molecular mechanical methods (MM+). The change in the structure of the molecule, expressed as a change in energy gain, conferred by the mutations was determined.

Results: The E148Q mutation caused deviation from the wild-type pyrin segment encoded by exon 2 by 1.15% and from the whole pyrin molecule by 0.75%, comparable to the R202Q mutation and less than the M694V mutation which caused a deviation from the wild-type structure of the whole pyrin molecule by 1.5%.

Conclusions: A quantum-chemistry based model suggests that the structural effect of the E148Q mutation is indeed low, but not zero. 
 

Background: Amyloidosis of familial Mediterranean fever (FMF) may lead to end-stage renal failure, culminating in kidney transplantation. Since amyloidosis is prompted by high serum amyloid A (SAA) levels, increased SAA is expected to persist after transplantation. However, no data are available to confirm such an assumption.

 Objectives: To determine SAA levels in kidney-transplanted FMF-amyloidosis patients and evaluate risk factors for the expected high SAA levels in this patient group.

Methods: SAA, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) values were obtained from 16 kidney-transplanted FMF-amyloidosis patients, 18 FMF patients without amyloidosis and 20 kidney-transplanted patients with non-inflammatory underlying disease. Demographic, clinical and genetic risk factors evaluation was based on data extracted from files, interviews and examination of the patients.

Results: SAA level in FMF patients who underwent kidney transplantation due to amyloidosis was elevated with a mean of 21.1 ± 11.8 mg/L (normal ≤ 10 mg/L). It was comparable to that of transplanted patients with non-inflammatory disorders, but tended to be higher than in FMF patients without amyloidosis (7.38 ± 6.36, P = 0.08). Possible risk factors for the elevated SAA levels in kidney transplant patients that were excluded were ethnic origin, MEFV mutations, gender, age and disease duration.

Conclusions: Kidney-transplanted patients with FMF-amyloidosis and with other non-FMF causes displayed mildly elevated SAA levels, possibly resulting from exposure to foreign tissue rather than from various FMF-related factors. 

Background: Since the identification of the MEFV gene 198 mutations have been identified, not all of which are pathologic. The screening methods used in Israel to test patients suspected of having FMF include a kit that tests for the five main mutations (M694V, V726A, M680Ic/g, M694I, E148Q), and the sequencing of MEFV exon 10 in combination with restriction analysis for detecting additional mutations.

Objectives: To determine the contribution of testing for five additional mutations – A744S, K695R, M680Ic/t, R761H and P369S – to the molecular diagnosis of patients clinically suspected of having FMF.

Methods: A total of 1637 patients were tested for FMF mutations by sequencing exon 10 and performing restriction analysis for mutations E148Q and P369S.

Results: Nearly half the patients (812, 49.6%) did not have any detectable mutations, 581 (35.5%) had one mutation, 241 (14.7%) had two mutations, of whom 122 were homozygous and 119 compound heterozygous, and 3 had three mutations. Testing for the additional five mutations enabled us to identify 46 patients who would have been missed by the molecular diagnosis kit and 22 patients who would have been found to have only one mutation. Altogether, 4.3% of the patients would not have been diagnosed correctly by using only the kit that tests for the five main mutations.

Conclusions: This study suggests that testing for the additional five mutations as well as the five main mutations in patients with a clinical presentation of FMF adds significantly to the molecular diagnosis of FMF in the Israeli population.
 

Intussuception is the most common cause of intestinal obstruction in early childhood. The cause of most intussusceptions is unknown but it can complicate the course of Henoch-Schonlein purpura (HSP) as a result of the vasculitic process. Familial Mediterranean fever (FMF), a most common disease in Israel is also associated with HSP. In a few patients, particularly in children, HSP has been reported to precede the diagnosis of FMF. We describe two patients with an unusual clinical course of severe abdominal pain as a result of intusucception. The correlation between intusucception, HSP and FMF are discussed.
 

Background: The new syndrome, known as PFAPA, of periodic fever characterized by abrupt onset of fever, malaise, aphthous stomatitis, tonsillitis, pharyngitis and cervical adenopathy  has been described only in pediatric patients. It usually begins before the age of 5 years and in most cases resolves spontaneously before age 10. 

Objectives: To describe a series of adults with PFAPA syndrome.

Methods: This 6 year retrospective descriptive study includes all newly diagnosed incident adult cases aged 18 years and over referred to our center with symptomatology suggestive of PFAPA syndrome. Patients’ medical records were reviewed for past history of the disease, demographic characteristics, symptoms and signs, course of the disease, laboratory findings, and outcome following corticosteroid therapy. The comparison group included our pediatric cohort children (N=320, age 0–18 years) followed for the last 14 years (1994–2008).

Results: Fifteen adult patients were diagnosed with PFAPA syndrome. Episodes of fever occurred at 4.6 ± 1.3 week intervals, beginning at the age of 20.9 ± 7.5.  All patients had monthly attacks at the peak of the disease, with attacks recurring at 4–8 week intervals over the years. Between episodes the patients were apparently healthy, without any accompanying diseases. Attacks were aborted by a single 60 mg dose of oral prednisone in all patients.

Conclusions: This study reports the presence of PFAPA syndrome in adult patients. Although the disease is rare, an increased awareness by both patients and family physicians of this clinical syndrome has resulted in more frequent diagnosis in adult patients.
 

Backgound: Colchicine is widely used for treating gout and familial Mediterranean fever. However, studies in animal models have reported ill effects of colchicine on the central nervous system, including cognitive function.

Objectives: To evaluate the cognitive status of elderly FMF[1] patients on long-term colchicine treatment.

Methods: The study group consisted of 55 FMF patients aged 74 ± 5, attending an FMF outpatient clinic and receiving colchicine treatment for 25.1 ± 8.9 years. The Mini-Mental State Examination was used for cognitive evaluation. Patients' scores were compared with accepted age- and education-adjusted cutoff scores, population-based norms, and scores of a matched control group of 56 subjects.

Results: Individually, all colchicine-treated FMF patients scored well above the age- and education-corrected cutoff scores. Overall, there was a large difference, 5.0 ± 1.6, from the expected cutoff points, in favor of the study group scores (P < 0.001). The individual scores of the control group were also above the cutoff points, however with a lower but still statistically significant difference (3.71 ± 1.15 points, P < 0.001). Compared to population-based norms adjusted by age and education, the study group had significantly higher mean MMSE[2] scores (27.2 ± 2.2 vs. 25.5 ± 2.4, P < 0.001). The control group’s scores were also somewhat higher than expected, but not significantly so.

Conclusions: Our results do not support the view that prolonged colchicine treatment may be associated with cognitive impairment. On the contrary, it is possible that long-term colchicine treatment may even confer protection against cognitive decline in patients with FMF.

Background: Familial Mediterranean fever is an autosomal recessive disease characterized by recurrent attacks of fever and serositis. The disease is caused by mutations in the MEFV gene, presumed to act as a down-regulator of inflammation within the polymorphonuclear cells.

Objectives: To present the results of 412 FMF patients genotyped for three MEFV mutations, M694V, V726A and E148Q.

Results: The most frequent mutation, M694V, was detected in 47% of the carrier chromosomes. This mutation, especially common among North African Jewish FMF[1] patients, was not found in any of the Ashkenazi (East European origin) patients. Overall, one of the three mutations was detected in 70% of the carrier chromosomes. M694V/M694V was the most common genotype (27%), followed by M694V/V726A (16%). The full genotype could be assessed in 57% of the patients, and one disease-causing mutation in an additional 26%. Only one patient with the E148Q/E148Q genotype was detected despite a high carrier rate for this mutation in the Jewish population, a finding consistent with a low penetrance of this genotype. The M694V/M694V genotype was observed in 15 patients with amyloidosis compared to 4 amyloidosis patients with other genotypes (P < 0.0001).

Conclusions: Because of low penetrance and as yet other undetermined reasons, mutation analysis of the most common MEFV mutations supports a clinical diagnosis in only about 60% of patients with definite FMF.

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