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Less than 30 cases of Dysosteosclerosis have been reported in the literature to date.

The disease is characterized by sclerosis of the skull base, ribs, clavicles, scapulae, mid-diaphyses and increased bone fragility. Patients have a prominent forehead, narrow midface, flattening of the vertebral bodies and dental anomalies. Short stature, optic atrophy, hearing impairment, epilepsy, skin changes, and progressive psychomotor deficit are frequent.

The disease is caused by mutations in SLC29A3. This gene encodes a nucleoside transporter. Mutations in this gene may also cause Faisalabad histiocytosis, Rosai-Dorfman disease, H syndrome, and pigmented hypertrichosis with insulin-dependent diabetes mellitus syndrome. Parental consanguinity has been noted in some cases. Mutations in osteopetrosis genes TNFRSF11A and TCIRG1 can also cause dysosteosclerosis.

Sequencing combined by deletion and duplication analysis is possible.

Osteopetrosis is more common than dysosteosclerosis and distinguishing features are the presence of sclerotic platyspondyly as well as widened and relatively radiolucent sub-metaphyseal regions of long tubular bones with sclerotic diaphysis. Responsible genes include OSTM1, SNX10, CA2, TCIRG1, TNFSF11, CLCN7, PLEKHM1, TNFRSF11A, and LRP5. In Pyle disease, there is important metaphyseal expansion with cortical thinning of the tubular bones well into the diaphyses. There can be mild platyspondyly and skull sclerosis but not as much as in dysosteosclerosis. Genu valgum is a key clinical feature. The responsible gene is SFRP4. In BANDDOS (Brain abnormalities, neurodegeneration, and dysosteosclerosis), there are bone changes similar to dysosteosclerosis, osteopetrosis or Pyle disease, but there is also neurological disease of neonatal, childhood or adult onset. The responsible gene is CSF1R.

Dysosteosclerosis is inherited in an autosomal recessive manner for SLC29A3, TNFRSF11A and TCIRG1 mutation. An X-linked pedigree has also been reported.

Management is mostly supportive, bone marrow transplantation was tried in one individual without success.

The overall prognosis is generally poor, although, as in osteopetrosis, there is a wide spectrum of severity.