Diagnosing Familial Mediterranean Fever and Assessing Amyloidosis Risk with the FMF StripAssay

Introduction

Familial Mediterranean Fever (FMF) remains the most prevalent inherited inflammatory disorder, predominantly impacting populations of Mediterranean descent. Characterized by periodic episodes of fever and acute inflammation, the disorder can escalate into severe complications, notably systemic reactive (AA) amyloidosis, which potentially leads to organ failure. One of the groundbreaking advancements in the diagnosis and risk assessment of FMF and associated amyloidosis is the FMF StripAssay®.

Clinical Significance of FMF

FMF originates from mutations in the MEFV gene, responsible for the synthesis of a protein known as pyrin or marenostrin. These mutations exert a variable influence on the clinical manifestations of FMF, as well as on the risk for developing AA amyloidosis. The medical community currently relies on colchicine as a prophylactic treatment, reducing the occurrence of amyloidosis and enabling patients to maintain a normal life quality.

The Amyloidosis Factor

Amyloidosis results from the extracellular deposition of serum amyloid A (SAA) fragments, culminating in irreversible organ damage. It is of note that the homozygous condition of the SAA isotype SAA1.1 is associated with an elevated risk of developing AA amyloidosis in FMF patients.

A Closer Look at FMF StripAssay®

The FMF StripAssay® leverages reverse-hybridization of biotinylated PCR products and utilizes allele-specific oligonucleotides immobilized on a test strip. The detection of bound biotinylated sequences is accomplished using streptavidin-alkaline phosphatase and color substrates, with the outcomes easily discernible to the naked eye.

Analytical Procedure

The FMF StripAssay® follows a tripartite analytical framework:

1. Amplification: This entails Multiplex PCR that simultaneously labels biotin.
2. Hybridization: Conducted directly on the StripAssay® test strips.
3. Identification: The biotin-labelled sequences are detected through a streptavidin-alkaline phosphatase reaction, either by visual inspection or specialized scanner and software.

Utility in Medical Practice

The assay is intended for the clinical identification of mutations in the MEFV gene, based on a highly reliable methodology that encompasses DNA isolation, PCR amplification, and reverse-hybridization. It has the capability to cover 12 mutations in the MEFV gene, thereby offering an exhaustive view of FMF and its associated risk factors.

In conclusion, the FMF StripAssay® is a useful tool for diagnosing Familial Mediterranean Fever and assessing amyloidosis risk. With its CE-IVDR certification, it serves as a reliable replacement for homebrew kits in diagnosing this particular genetic disorder.