Adult-onset systemic autoinflammatory disorders: a clinical approach

Variables for differential diagnosis of familial Mediterranean fever: Multiple correspondence analysis of a large Japanese cohort

OBJECTIVES

We investigated differential diagnoses that should be noted with familial Mediterranean fever (FMF) and useful variables for differentiation in a large Japanese cohort.

METHODS

Patients aged ≥13 years who were clinically suspected of having FMF by Livneh criteria were studied 1 year after MEFV genetic testing. Patients ultimately diagnosed with other diseases were studied, and the association among each disease, patient characteristics, and clinical variables were analysed using multiple correspondence analysis.

RESULTS

In total, 504 patients were included in this study; 34 (6.7%) were diagnosed with a disease other than FMF. The most common diagnosis was Behçet's disease, followed by periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome, inflammatory bowel disease, myelodysplastic syndromes (MDS), and infectious diseases. Although none of the non-FMF patients had exon 10 variants, some responded to colchicine treatment. Multiple correspondence analysis suggested that atypical symptoms such as stomatitis were associated with Behçet's disease and PFAPA syndrome, whereas characteristic situations such as disease onset ≥40 years were associated with MDS and infectious diseases.

CONCLUSION

Careful follow-ups and reanalysis of the diagnosis should be performed for patients with atypical findings and no exon 10 variants, even if their symptoms meet the clinical criteria for FMF.

The Clinical Chameleon of Autoinflammatory Diseases in Children

The very first line of defense in humans is innate immunity, serving as a critical strongpoint in the regulation of inflammation. Abnormalities of the innate immunity machinery make up a motley group of rare diseases, named ‘autoinflammatory’, which are caused by mutations in genes involved in different immune pathways. Self-limited inflammatory bouts involving skin, serosal membranes, joints, gut and other districts of the human body burst and recur with variable periodicity in most autoinflammatory diseases (ADs), often leading to secondary amyloidosis as a long-term complication. Dysregulated inflammasome activity, overproduction of interleukin (IL)-1 or other IL-1-related cytokines and delayed shutdown of inflammation are pivotal keys in the majority of ADs. The recent progress of cellular biology has clarified many molecular mechanisms behind monogenic ADs, such as familial Mediterranean fever, tumor necrosis factor receptor-associated periodic syndrome (or ‘autosomal dominant familial periodic fever’), cryopyrin-associated periodic syndrome, mevalonate kinase deficiency, hereditary pyogenic diseases, idiopathic granulomatous diseases and defects of the ubiquitin-proteasome pathway. A long-lasting history of recurrent fevers should require the ruling out of chronic infections and malignancies before considering ADs in children. Little is known about the potential origin of polygenic ADs, in which sterile cytokine-mediated inflammation results from the activation of the innate immunity network, without familial recurrency, such as periodic fever/aphthous stomatitis/pharyngitis/cervical adenopathy (PFAPA) syndrome. The puzzle of febrile attacks recurring over time with chameleonic multi-inflammatory symptoms in children demands the inspection of the mixture of clinical data, inflammation parameters in the different disease phases, assessment of therapeutic efficacy of a handful of drugs such as corticosteroids, colchicine or IL-1 antagonists, and genotype analysis to exclude or confirm a monogenic origin.

Rare genetic causes of meningitis and encephalitis

Differential diagnosis of meningitis and encephalitis is often very challenging because it cannot be determined based on symptoms, and the diseases have various causes. This article explains rare genetic causes of meningitis and encephalitis. Autoinflammatory disorders include cryopyrin-associated periodic syndromes, familial Mediterranean fever, and tumor necrosis factor receptor-associated periodic syndrome. Furthermore, other genetic disorders, such as complement factor I deficiency, phosphatidylinositol glycan anchor biosynthesis class T mutation, and neuronal intranuclear inclusion disease, can present as meningitis and encephalitis.

Transient and Recurrent Pulmonary Infiltrations Associated with Familial Mediterranean Fever

Chest symptoms and pleural effusion due to serositis in familial Mediterranean fever (FMF) are occasionally misdiagnosed as acute pneumonia. However, the actual pulmonary involvement of FMF is extremely rare. A 67-year-old man was referred to our hospital due to repeated and transient anterior chest pain. Chest images revealed a moderate amount of pericardial fluid, slight bilateral pleural effusion, and infiltrations in both lower lung lobes. Colchicine treatment without antibiotics rapidly improved these symptoms and findings. Pericarditis, pleurisy and the response to colchicine indicated FMF. FMF should be considered as a causative disease of pulmonary infiltrations, especially if it occurs repeatedly.

Efficacy and safety of canakinumab in the treatment of adult-onset Still's disease: A systematic review

BACKGROUND

Adult-onset Still's disease (AOSD) is a rare inflammatory disease, typically characterized by spiking fever, skin rash, and arthralgia or arthritis. Its conventional treatment includes NSAIDs and corticosteroids, and DMARDs as second-line therapy. Frequently, IL-1 inhibitors are also required, mainly in patients refractory to traditional therapy. Canakinumab is a monoclonal antibody that binds IL-1β with high affinity and specificity, making it appropriate for therapeutic purposes in AOSD.

OBJECTIVE

The aim of this systematic review was to identify and compile the current data on the efficacy and safety of canakinumab in the treatment of AOSD.

METHODS

Following the guidelines established by the PRISMA statement, we searched Scopus, Web of Science, Pubmed, and Cochrane Library for relevant literature up to March 2021. The inclusion criteria comprised: randomized controlled trials, pooled analyses, observational studies, case series, and case reports.

RESULTS

Seventeen studies published from 2012 to 2021 were evaluated; 11 of these correspond to case series or case reports, four observational studies, one placebo-controlled phase II trial, and one analysis of pooled systemic juvenile idiopathic arthritis data. In general, out of a total of 99 patients, 68.7% of these presented a complete remission of the systemic and arthritic manifestations at the end of the observation period, while 16.2% of the patients showed a partial improvement of the symptoms and the remaining (15.1%) did not show clinical improvement or were excluded. Moreover, 210 adverse events were reported in 69 patients during canakinumab treatment, of which the majority correspond to respiratory tract infections, arthralgia, disease flares, abdominal pain, nausea, and diarrhea, whereas the most common severe adverse events included macrophage activation syndrome and serious infections. Also, a corticosteroid-sparing effect was observed in a large percentage of patients.

CONCLUSION

More studies with solid evidence are needed to support the efficacy of canakinumab in AOSD, although its use is encouraged by the increasing favorable results reported and the efficacy of other IL-1 inhibitors. It was also associated with an acceptable safety profile, similar to expected in IL-1 inhibitor therapy. However, future studies with well-defined endpoints are warranted to examine further the usefulness of canakinumab in AOSD.