Pharmacokinetics and Colchicine in Pediatric and Adult Patients with Familial Mediterranean Fever

This study sought to determine the appropriate starting dose of colchicine in children aged 2 to 4 years with familial Mediterranean fever (FMF) based on steady-state pharmacokinetics in pediatric patients with FMF ⩾2 to <16 years and adult patients with FMF ⩾16 to ⩽65 years. Outpatients received colchicine for 90 days starting with a fixed dose for 14 days (blood sampling days 14 and 15). After starting doses of colchicine (0.6 mg/day [⩾2 to <4 years], 0.9 mg/day [⩾4 to <6 years], 0.9 mg/day [⩾6 to <12 years], 1.2 mg/day [⩾12 to <16 years], and 1.2 mg/day [⩾16 to ⩽65 years]), the observed steady-state pharmacokinetic parameters were comparable across age groups, despite the higher doses of colchicine on a mg/kg/day basis in the younger age groups. An exception occurred with once-daily colchicine, whereby mean Cmax for colchicine was higher in patients 4 to <6 years (9.4 ng/mL) compared with the younger and older age groups (6.1–6.7 ng/mL). Mean AUC0-24h values in children 2 to <4, 6 to <12, and 12 to <16 years were similar to those in adults. However, mean AUC0-24h values in children 4 to <6 years were 25% higher than those observed in adults. The results show that the recommended starting dose for children 2–4 years and 4–6 years should be 0.6 mg/day (half the US adult dose). Children aged 6 to <12 years should receive 0.9 mg/day (i.e. three-quarters of the US adult dose). The safety of colchicine in children 2 to <4 years was comparable to that in older children and adults.

Guidelines for the genetic diagnosis of hereditary recurrent fevers

Hereditary recurrent fevers (HRFs) are a group of monogenic autoinflammatory diseases characterised by recurrent bouts of fever and serosal inflammation that are caused by pathogenic variants in genes important for the regulation of innate immunity. Discovery of the molecular defects responsible for these diseases has initiated genetic diagnostics in many countries around the world, including the Middle East, Europe, USA, Japan and Australia. However, diverse testing methods and reporting practices are employed and there is a clear need for consensus guidelines for HRF genetic testing.

Draft guidelines were prepared based on current practice deduced from previous HRF external quality assurance schemes and data from the literature. The draft document was disseminated through the European Molecular Genetics Quality Network for broader consultation and amendment. A workshop was held in Bruges (Belgium) on 18 and 19 September 2011 to ratify the draft and obtain a final consensus document. An agreed set of best practice guidelines was proposed for genetic diagnostic testing of HRFs, for reporting the genetic results and for defining their clinical significance.

Familial Mediterranean fever gene (MEFV) mutations as a modifier of systemic lupus erythematosus

The objective of this study was to assess the prevalence of the Mediterranean FeVer ( MEFV) gene mutations in systemic lupus erythematosus (SLE) patients and their effect on organ involvement, as well as disease activity and severity. The frequencies of three familial Mediterranean fever-related MEFV gene mutations ( M694V, V726A and E148Q) were investigated in 70 SLE patients. Organ involvement, Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index and Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores were correlated with mutation carriage. Eleven of 70 patients (15.7%) were found to carry an MEFV mutation. A single patient harbored two mutations, E148Q and V726A, without overt familial Mediterranean fever while the rest were heterozygous carriers. Four of the 11 carried an M694V mutation, four carried V726A and two carried E148Q. The majority of MEFV mutation carriers were Sephardic while non-carriers were mainly of Ashkenazi origin (72.7% vs. 45.7% and 47.4% vs. 9.1%, respectively, p = 0.02). SLE onset was significantly earlier in MEFV carriers (27.6 ± 9.7 vs. 38.2 ± 15.5 years, in carriers vs. non-carriers, p = 0.02). Hematologic and serologic parameters were comparable among mutation carriers and non-carriers. Febrile episodes were more common among MEFV mutation carriers (45.4% vs. 15.2%, p = 0.035) and there was a trend for excess episodes of pleuritis as well (54.5% vs. 23.7%, p = 0.06 in carriers vs. non-carriers, respectively). The frequency of secondary anti-phospholipid antibody syndrome was equivalent among the groups. Conversely, compound urinary abnormalities and renal failure was not observed among MEFV carriers yet was present in 33.4% and 18.6% of non-carriers ( p = 0.027 and 0.19, respectively). SLICC damage index and SLEDAI activity index did not differ significantly between the groups. MEFV mutation carriage appears to modify the SLE disease phenotype in that it contributes to an excess of inflammatory manifestations such as fever and pleuritis on the one hand, while thwarting more severe renal involvement on the other.

'Silent' carriage of two familial Mediterranean fever gene mutations in large families with only a single identified patient

The presence of two mutations in the familial Mediterranean fever gene, without overt familial Mediterranean fever (FMF), designated as phenotype III, predisposes to developing 'silent' AA amyloidosis, recognized as phenotype II, due to the absence of medical supervision and colchicine prophylaxis. We sought to determine the prevalence of phenotype III in large families with only one subject affected with FMF, in order to assess the population at risk for transformation to phenotype II. A total of seven large families were recruited for the study. Siblings were screened for MEFV mutations and underwent a clinical interview to assess for unrecognized FMF manifestations. Phenotype III, most commonly associated with a V726A/E148Q genotype, was detected in 10% of siblings of index cases from informative families, corresponding to a 10-fold increase in comparison to the expected rate in the general population (p < 0.01). Unnoticed 'FMF-like' manifestations were detected among two siblings in the five families in which the index case was heterozygous, but in none of the siblings of the homozygous index cases. The enrichment for phenotype III and detection of occult FMF in large families, in which only a single member is afflicted with FMF, mandates routine clinical evaluation and genetic screening of siblings.

Familial Mediterranean fever (FMF) and multiple sclerosis: an association study in one of the world's largest FMF cohorts

BACKGROUND AND PURPOSE

  To describe and characterize the association between familial Mediterranean fever (FMF) and multiple sclerosis (MS).

METHODS

  The patient registry of The National Center for FMF was screened for the coexistence of FMF and MS. Tel-Hashomer criteria were used for the diagnosis of FMF, and FMF severity was evaluated, using the simplified FMF severity scale. McDonald criteria were used for the diagnosis of MS, and neurologic disability was measured using the expanded disability status scale (EDSS).

RESULTS

  We identified nine patients, affected with both FMF and MS. The onset of the FMF averaged 15.6 (3-37) years. Most patients suffered from abdominal and joint attacks, and 50% of the patients sustained a moderate to severe FMF. The onset of the MS was at an average age of 31.6 (17-50) years. Neurologic manifestations varied individually, without a dominant deficit, and the course was in a relapsing-remitting pattern in most. The median EDSS was in general of low score (3.0), apart from the patients who were homozygous for the M694V mutation, in whom the MS was more severe. Based on our case series, the frequency of MS in our FMF population is 0.075%, twice higher the expected rate in the general population (P=0.0057).

CONCLUSIONS

  Multiple sclerosis is more common in FMF than in the general Israeli population. Homozygosity for the M694V MEFV mutation may aggravate the phenotype of MS and predispose FMF patients to develop MS.

Common FMF alleles may predispose to development of Behcet's disease with increased risk for venous thrombosis

BACKGROUND

Behcet's disease (BD) is an inflammatory disorder of unknown cause, associated with vasculitis. Arterial or venous thrombosis occurs in about 25% of BD patients. Familial Mediterranean fever (FMF) is another inflammatory disorder, which stems from mutations in the FMF gene (MEFV) and shares a number of features with BD.

OBJECTIVE

MEFV analysis in patients with BD suggests that mutated MEFV may act as a susceptibility gene in BD. We studied the rate and the clinical correlates of MEFV mutations in Israeli BD patients.

METHODS

Included were 54 BD patients who satisfied the International Study Group criteria for BD. All BD patients were genotyped using polymerase chain reaction (PCR) and restriction enzyme analysis for the three most common MEFV mutations (M694V, V726A, and E148Q). The association between BD manifestations and MEFV alleles was analysed.

RESULTS

Twenty-one BD patients were found to carry a single MEFV mutation and three additional patients were compound heterozygotes, a frequency significantly higher than that expected for ethnically matched healthy individuals. There were no statistically significant differences between carriers and non-carriers with respect to gender, frequency of HLA B5 antigen, cutaneous lesions, joint disease, and severity score. However, carriers did experience thrombosis more often [54% vs. 17%, p<0.005, odds ratio (OR) = 6.9, 95% confidence interval (CI) 1.75-26.9] and uveitis less often (20% vs. 40%, p<0.05, OR = 0.2, 95% CI 0.04-0.92).

CONCLUSIONS

MEFV appears to be a susceptibility and modifier gene in BD.

Appendectomy in familial Mediterranean fever: clinical, genetic and pathological findings

BACKGROUND

Abdominal attacks of familial Mediterranean fever (FMF) may simulate acute appendicitis and bring about considerable uncertainty. The similar presentation of the two clinical entities often leads to an unnecessary appendectomy.

METHODS

182 consecutive FMF patients were retrospectively reviewed for this study. Clinical and genetic data was compared between those who had undergone an appendectomy (n=71) and those who had not (n=111).

RESULTS

The frequency of appendectomy found in FMF was far above the reported rate in the general population (40% vs. 12-25%). The rate of non-inflamed appendectomies was extremely high (80% vs. 20%) and remained constant over time. Tertiary hospitals and improved therapeutic and diagnostic measures that have evolved over the years did not reduce misdiagnosis of acute appendicitis in FMF. Severe phenotype and homozygosity for M694V were identified as risk factors for appendectomy in FMF. A change from the regular diffuse involvement to right lower quadrant abdominal pain was found to be the best predictor of inflamed appendix in FMF patients undergoing appendectomy for suspected acute appendicitis.

CONCLUSION

Reliance on clinical parameters should improve diagnostic accuracy of acute appendicitis in the FMF patient population.

Systemic lupus erythematosus and familial Mediterranean fever: a possible negative association between the two disease entities – report of four cases and review of the literature

Serositis is a common clinical manifestation of systemic lupus erythematosus (SLE), as well as being the hallmark of familial Mediterranean fever (FMF), the most prevalent monogenic disease in the Jewish population. We have treated four patients who suffered from both SLE and FMF since 2001 in our clinic, which also serves as the national center for FMF. Our cases illustrate both similarities and dissimilarities between the clinical manifestations of these two diseases, an aspect which should be borne in mind, especially in the young female patients. In general, it seems that co-occurrence of FMF moderates the presentation of lupus.

Familial Mediterranean fever: clinical, molecular and management advancements

Familial Mediterranean fever (FMF), the most frequent of the periodic fever syndromes, is an autosomal recessive disease, predominantly affecting people of Mediterranean descent. The disease is caused by mutations in the MEFV gene, encoding the pyrin protein thought to be associated with the interleukin-1 related inflammation cascade. The condition manifests as attacks of serositis, commonly involving the abdomen, chest or joints, typically accompanied by fever and elevated acute phase reactants. Attacks subside spontaneously within one to three days, without residue. Continuous treatment with colchicine, at a daily dose of 1 to 2 mg, reduces attack frequency, duration and intensity in the majority of patients, and also prevents the development of secondary amyloidosis, the most dreaded complication of the disease. In this communication we review the current state of the art in the diagnosis and care of FMF patients, starting with the presentation of a typical case.