Progressive pseudorheumatoid arthritis of childhood (PPAC). A hereditary disorder simulating rheumatoid arthritis

Five patients are described with a hereditary arthropathy affecting major and minor joints. The main features of this progressive connective tissue disorder are restricted joint mobility, osseous swelling of the interphalangeal and other joints, and platyspondyly. The condition is commonly misdiagnosed as "chronic juvenile polyarthritis with Scheuermann disease". It differs from the rheumatoid-factor-negative polyarticular form of rheumatoid arthritis and other rheumatoid spondylarthropathies by the absence of arthritic and other inflammatory changes, radiographically by the absence of destructive and the presence of dysplastic bone changes. The disorder does not seem to respond to the usual forms of antirheumatoid treatment. Histological studies showed a peculiar, nest-like clustering of chondrocytes in the resting and growth cartilage suggesting that pathogenetically this is a primary disorder of the articular cartilage.

[Ankylosing spondylitis (Bechterew's disease)--a current review (author's transl)]

Ankylosing spondylitis is a disease with clinically and radiologically very variable features. It is the intention to direct the attention from the old by orthopedists' influenced association of the stiff back to the polymorphism of the disease especially to the early stages which still frequently are recognized too late. The paper deals with the nosology, the various states of the clinical course with the numerous radiological criteria including therapeutical approaches.

[Yersinia arthritis (author's transl)]

Yersinia arthritis is an acute oligo- or, more rarely, polyarthritis. It occurs after pyrexic diarrhoea of several days, often associated with right-sided lower abdominal pain. The disease is caused by Yersinia enterocolitica and four such cases, confirmed serologically in three, are described. In one case fluid from the knee-joint was antibody-positive. It was not possible to culture the causative organism, probably because all patients had previously been treated with an antibiotic. Rheumatic fever and Reiter's disease must be considered in the differential diagnosis. Because pharyngitis, transitory ECG changes and conjunctivitis may occur in the early stages of Yersinia arthritis, the diagnosis may be missed. Prognosis of Yersinia arthritis is good, with complete cure within weeks or months. Demonstration of HLA-B 27 in all four cases points to a genetic disposition.