[Adult-onset of Still's disease with atypical articular and skin manifestations]. / Atteintes articulaire et cutanée atypiques au cours d'une maladie de Still de l'adulte.

BACKGROUND: Adult-onset Still's disease (ASD) is an uncommon clinical entity. It is a diagnosis of exclusion, characterized by a clinical triad of intermittent fever spikes, evanescent rash, and either arthralgia or arthritis. Destructive arthritis more commonly affects the hips, wrists, tarsal joints and cervical spine. AIM: To report an unusual case of ASD with severe distal interphalangeal destructive arthritis and finger skin vesiculopustules. OBSERVATION: A 19 years old girl was followed for 2 year-history of ASD with polycyclic articular involvement. She noted, since 2 months, rapid appearance of painful tumefaction in the distal interphalangeal joints (DIP) with maculopustular eruption distributed exclusively on the hands, in front, only of DIP and few proximal interphalangeal joints (PIP). Further more, she complained of polyarticular active disease. Hands and wrists X-ray showed narrowed distal-interphalangeal joint space of only DIP joints. RMN imaging revealed in addition carpal, metacarpal and PIP articular inflammatory damage. The infectious investigation remained negative. A surgical skin and DIP biopsy specimens showed disseminated micro-abscesses with polynuclear leukocyte dermal infiltration. There was no signs of osteitis. Bacterial and fungal cultures from the pus failed to reveal any causative organisms. Skin lesions gradually disappeared in response to conventional ASD therapy after intensification. Hence, the diagnosis of distal destructive arthritis of ASD associated with atypical neutrophilic dermatosis (Sweet's syndrome) was made. CONCLUSION: ASD is rare, heterogeneous, with unpredictable evolution. The distal destructive arthritis represents a possible complication. The presence of pustules as atypical cutaneous features of Sweet's syndrome may be seen in severe forms of ASD and clinicians must be alert to the possibility of a misdiagnosis in these cases.

An autosomal dominant hypophosphatemic rickets phenotype in a Tunisian family caused by a new FGF23 missense mutation.

Autosomal dominant hypophosphatemic rickets (ADHR) is a rare disease, characterized by isolated renal phosphate wasting, hypophosphatemia, and inappropriately normal 1,25-dihydroxyvitamin D(3) (calcitriol) levels. This syndrome involves rickets with bone deformities in childhood and osteomalacia, osteoporosis, articular and para-articular pain, and fatigue in adulthood. It is caused by mutations in a consensus sequence for proteolytic cleavage of the FGF23 protein. Normally, this protein actively regulates phosphate homeostasis. Here we report a Tunisian family in which one parent and three children show clinical and biological features of ADHR. Mutation analysis of the FGF23 gene finds a heterozygous substitution of the C at position 526 by a T (526 C --> T), leading to an amino acid replacement of the FGF23 protein (R176W) at position 176. This causative new mutation is located in the consensus sequence for the proteolytic cleavage domain. These results confirm the importance of this site in FGF23 function and its essential role in ADHR physiopathology.

Prevalence of subclinical amyloidosis in Tunisian patients with rheumatoid arthritis.

INTRODUCTION: Secondary amyloidosis is a serious complication of rheumatoid arthritis (RA). Symptoms are late to occur, so that screening is in order, most notably in patients with long-standing RA. The objectives of our study were to determine the prevalence of subclinical amyloidosis in RA patients by abdominal fat aspiration biopsy (AFAB) and minor salivary gland biopsy (MSGB) and to identify factors associated with subclinical amyloidosis. METHODS: We prospectively studied 107 consecutive patients with RA (94 women and 13 men) recruited between March 2005 and January 2006. Clinical and laboratory findings, imaging study results, and treatment were recorded for each patient. AFAB and MSGB were performed routinely. Amyloid deposits were identified by polarized light microscopy after Congo red staining. RESULTS: The prevalence of subclinical amyloidosis was 21.5% by AFAB and 3.7% by MSGB. Factors associated with subclinical amyloidosis were a longer time to diagnosis (P=0.03), extraarticular manifestations (P=0.019), proteinuria >0.3 g/24 h (P=0.024), and absence of methotrexate therapy (P=0.046). Subclinical amyloidosis was not associated with age, sex, RA duration, joint deformities, DAS28 score, Health Assessment Questionnaire score, Steinbrocker radiological stage, rheumatoid factor, erythrocyte sedimentation rate, C-reactive protein, creatinine, or hemoglobin. CONCLUSION: The prevalence of subclinical amyloidosis by AFAB is high (21.5%). AFAB is more sensitive than MSGB for detecting subclinical amyloidosis. A simple screening tool such as AFAB should be used, particularly in patients with risk factors. Subclinical amyloidosis requires close monitoring to ensure the early detection and treatment of symptomatic amyloidosis.