Case of the Month
“Thigh Lesion …in a Thai Farmer”
A disease simulation using GIDEON's diagnosis module.
A 45 year old Thai farmer develops severe pain and swelling of the right leg. Symptoms began several weeks after he had begun work to clear out swampy undergrowth next to his village. The entire right leg is cold and swollen, and an ulcer is present on the inner aspect of the thigh. What is your diagnosis?
The clinical findings were entered into GIDEON:
… and the diagnosis result was:
Have you ever heard of Pythiosis?
GIDEON’s epidemiology module notes the following:
Pythiosis is just one of the 338 diseases covered in GIDEON – many of which have been described in only a handful of patients, or in a single country!
The following text is from the Pythiosis note in <Worldwide>:
Human pythiosis was first reported in Thailand, in 1987. The disease is reported primarily in tropical and subtropical regions. The etiologic agent is Pythium insidiosum, a fungus-like, aquatic organism found in animals and water plants. Natural infection of dogs, cats, cattle, horses and other mammals has been described in the United States, Thailand, Australia, Japan, Brazil, Colombia and Costa Rica.
Thirty-two cases of human infection had been published as of 2002, 25 of these in Thailand - over 90% of these farmers. Additional cases were reported in the United States and Brazil. Approximately 50% of published cases were classified as arterial, 25% ocular, and the remainder cardiopulmonary or cutaneous. Pythiosis is usually characterized by erosive and occlusive disease of major arteries, with occasional systemic spread. Severe keratitis progressing to endophthalmitis is also reported. Patients with arterial pythiosis usually have underlying hematologic disorders such as thalassemia, aplastic anemia or paroxysmal nocturnal hemoglobinuria.
