Physicians Asked to be on the Lookout for Possible “Hemorrhagic Pneumonia Cases”
Among Influenza Patients
The CDC says that there have been some anecdotal reports of possible "hemorrhagic pneumonia" cases among influenza patients who have died or been
hospitalized for severe illness. The phrase "hemorrhagic pneumonia" is somewhat outdated, and most clinicians will not use the term to describe this
condition, which can be a very rare complication of viral respiratory infection. Some other terms that can be used to
describe this include diffuse alveolar hemorrhage (DAH), which can be caused by infections but doesn't have to be, and hemorrhagic pneumonitis. In
any event, it's a serious complication that will sometimes lead to acute respiratory distress syndrome (ARDS). It occurs very rarely as a
complication of seasonal influenza, and there is some
concern that it might be more common in H1N1 infections.
The CDC is asking state health officials to look out for possible cases that may involve clusters of patients who might have these symptoms, or a
large proportion of cases with these symptoms (e.g., 4 of 5 deaths). They will invariably be among the most severely ill
influenza patients (i.e., deaths, ICU patients).