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DSH has been reported mainly in eastern Asia including Japan, although genetically confirmed DSH cases have also been reported in Thai, Indian, European, and Hispanic populations. The prevalence of DSH in Japan is estimated to be approximately 1/67,000 people. There does not appear to be male or female predominance. Pathogenic ADAR was also observed in the American population based on a genetic mutation database which implies that DSH patients might be found in the United States.

The first manifestations of the disease generally appear during early childhood and 70% of patients show eruptions until the age of 7. The eruptions might be exacerbated until the age of 20. Skin manifestations on the hands of DSH patients tend to worsen in summer. Quantitative analysis of seasonal changes in DSH severity revealed that sun exposure is only a transiently aggravating factor.

The disease is caused by monoallelic mutations in double-stranded RNA-specific adenosine deaminase 1 (ADAR1) gene. Biallelic ADAR1 mutations may also cause a form of Aicardi-Goutières syndrome (a severe genetic inflammatory disease in childhood that affects the brain and the skin, and mimics viral infection) or bilateral striatal necrosis (affecting the central nervous system).

Diagnosis is suspected on clinical presentation and confirmed by genetic testing. Although DSH shows autosomal dominant inheritance with nearly complete penetrance, intrafamilial variation of severity of skin manifestation can be seen. Thus, ultraviolet light examination can be useful to check the slight skin manifestation.

The differential diagnosis includes xeroderma pigmentosum, dyschromatosis universalis hereditaria, reticulate acropigmentation of Kitamura and Aicardi-Goutières syndrome caused by ADAR1 mutations.

Prenatal diagnosis is possible where the pathogenic variant has previously been identified in a family member.

The disorder is autosomal dominant; some cases occur sporadically. Genetic counseling should be offered to affected individuals informing them that there is a 50% risk of having an affected child at each pregnancy. The genetic penetrance is almost 100%.

There is no curative treatment. Topical sunscreen and sun-protective clothing can help to control the skin lesions.

DSH patient usually have a normal life expectancy.