Procreation perpetuates the mutations, resulting in an increased number of genetic defectives in subsequent generations. When the cerebral or GI syndrome is present, diagnosis is simple, but the prognosis is grave. Death results within hours to a few days in the cerebral syndrome and usually in 3 to 10 days in the GI syndrome. In the hematopoietic syndrome, death may occur in 8 to 50 days, in 2 to 4 wk due to a supervening infection, or in 3 to 6 wk due to massive hemorrhage. For a person who is receiving radiation therapy or has been exposed during a radiation accident, diagnosis is obvious.
Prognosis depends on dose, dose rate, and body distribution.
Serial hematologic and bone marrow studies to gauge the severity of bone marrow injury provide additional prognostic information. For chronic radiation injury in which external exposure is unknown or overlooked, a diagnosis may be difficult or impossible. Possible occupational exposure must be sought. In institutions licensed by federal or state governments, records of exposure to radiation are maintained. Serial chromosome studies can be performed to detect types and frequency of chromosomal abnormalities likely to occur after significant exposure, but these abnormalities may have preexisted or have other causes.