Far East scarlet-like fever

These include^[2][3]


Other features include mesenteric lymphadenitis and arthritis. Kidney failure rarely occurs. Relapses occur in up to 50% of patients. Enterocolitis is common in children. Sepsis occasionally occurs; it primarily occurs in patients with preexisting comorbidities such as diabetes mellitus, liver cirrhosis, or hemochromatosis. Postinfective complications include reactive arthritis, erythema nodosum, iritis, and glomerulonephritis.

Pathophysiology[edit]

The clinical features of this disease appear to be due—at least in part—to the production of a superantigen—YpM (Yersinia pseudotuberculosis-derived mitogen). This is present in almost all strains from the Far East but only 20% of European isolates.^[5] The antigen was discovered in 1993 and is encoded by a 456-base gene. The protein has 151 amino acids, with a signal sequence of 20 amino acids. The mitogenic antigens are scattered across the protein but two cysteine residues (residues 32 and 129) which form a disulfide bridge are critical.


The G+C content of this gene is 35%—lower than the genomic average (47%) suggesting that this gene has been acquired from some other organism.^[5] The organism from which this gene originated has not yet been identified. This gene seems likely to have been introduced into the genome by a bacteriophage, given the nearby presence of a phage integration site, but the mechanism of entry into the genome is not currently known.