| Clinical
Features |
Profuse and chronic watery diarrhea
typically associated with urgency and incontinence that begins
acutely and lasts from 2-36 months. |
| Etiologic
Agent |
Unknown. |
| Incidence |
An estimated 5,000-8,000 patients
with chronic diarrhea clinically similar to Brainerd diarrhea
are cared for by U.S. gastroenterologists each year. Approximately
every 3 years, CDC investigates an outbreak of Brainerd diarrhea
affecting 50-100 people. |
| Sequelae |
No known sequelae; however, many
people suffer adverse psychologic consequences related to
the long duration of an incapacitating illness. |
| Transmission |
Untreated water has been implicated
in several outbreaks and unpasteurized cow’s milk has been
implicated in one. |
| Risk
Groups |
The elderly appear to be at greatest
risk for Brainerd diarrhea, although several cases among children
and young adults have been described. |
| Surveillance |
No surveillance system exists for
Brainerd diarrhea or for other chronic diarrheal syndromes
of unknown etiology (e.g., collagenous colitis, microscopic
colitis). |
| Trends |
Data are insufficient to indicate
an increase or decrease in incidence. |
| Challenges |
Despite numerous intensive laboratory
investigations, the etiologic agent of Brainerd diarrhea remains
a mystery. Histologic criteria for distinguishing Brainerd
diarrhea from other chronic diarrheal syndromes were developed
from outbreak-related specimens, but need to be evaluated
in specimens from patients with sporadic cases of chronic
idiopathic secretory diarrhea. |
| Opportunities |
Newer techniques, such as ribosomal
RNA amplification on sterile site tissue biopsies may shed
new light on the etiologic agent. The histologic criteria
can be tested against specimens from a recent outbreak. |
|
December 2003
|
