Manifest illness stage is the period when symptoms that affect the hematopoietic, gastrointestinal, and cerebrovascular systems become visible during the major response stages of acute radiation syndrome after the prodromal stage.
Explanation:
Acute radiation syndrome (ARS) due to radiation toxicity affects the parenchymal cells of specific tissues. According to the tissue system affected, the ARS typically presents either as bone marrow (hematopoietic), gastrointestinal, or cardiovascular syndrome.
The four major response stages of acute radiation syndrome are – Prodromal, latent, manifest illness, recovery or death.
Although the stage next to prodromal stage is latent stage, the symptoms manifests itself during the manifest illness stage. The manifestation, severity and recovery of symptoms vary with each syndrome.
Symptom manifestation during manifest illness stage
Hematopoeitic ARS – drop in blood cell count, hemorrhage, anorexia, malaise
Gastrointestinal ARS – anorexia, diarrhea, dehydration, fever, electrolyte imbalance
Cardiovascular/central nervous system ARS – convulsions, coma