Chronic Recurrent Multifocal Osteomyelitis

Clinical Features

Giedion et al. (1972) described a syndrome termed chronic recurrent multifocal osteomyelitis (CRMO). The inflammation had both subacute and chronic features, with lesions located predominantly in the metaphyses of the long bones. No pathogens were isolated from affected areas.

Multifocal osteomyelitis associated with pustulosis has also been described (see 612852).

Mapping

Golla et al. (2002) genotyped 27 patients with CRMO and their parents, using the markers D18S1148 and D18S60 within the region homologous to the mouse cmo (PSTPIP2; 616046) locus. A significant association of CRMO with a rare allele of marker D18S60 was found, resulting in a haplotype relative risk (HRR) of 18. No pathogenic mutations were detected in the TNFRSF11A (603499) and PIGN (606097) genes, which map to the chromosome 18q21-q22 region. Although the genetic model of CRMO was not clear, the high HRR suggested that the gene underlying the observed association contributes to the etiology of CRMO and concomitantly demonstrated evidence for a genetic basis of CRMO.

Animal Model

Byrd et al. (1991) identified a disorder in mice that had features similar to those described by Giedion et al. (1972). The phenotype was first recognized in mice with tail kinks and deformities of the hindlimbs. Breeding analysis showed that the defect was determined by a single autosomal recessive mutation. RFLP analysis of a linkage backcross indicated that the cmo gene resided on mouse chromosome 18. As in humans, no known pathogen could be isolated from the lesions.

Ferguson et al. (2006) described the CRMO phenotype in the cmo mouse, which includes bone, cartilage, and skin inflammation of the extremities and ears. They identified an L98P mutation in the Pstpip2 gene and suggested that this may be the cause of the autoinflammatory phenotype.