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Intestinal myiasis
U S Udgaonkar1, R Dharamsi, S A Kulkarni
1Department of Microbiology, Bharati Vidyapeeth Deemed University Medical College and Hospital, Sangli, Maharashtra, India.
Purpose:
Intestinal myiasis is a condition when the fly larvae inhabit the gastrointestinal tract and are passed out in faeces. This type of infestation results when eggs or larvae of the fly, deposited on food are inadvertently taken by man. They survive the unfavourable conditions within the gastrointestinal tract and produce disturbances, which may vary from mild to severe. The condition is not uncommon and is often misdiagnosed as pinworm infestation. Correct diagnosis by the clinical microbiologist is important to avoid unnecessary treatment.
Materials And Methods:
We had 7 cases of intestinal myiasis. In 2 cases the larvae were reared to adult fly in modified meat and sand medium (developed by Udgaonkar). This medium is simple and can be easily prepared in the laboratory.
Results:
Of the 7 larvae, 5 were Sarcophaga haemorrhoidalis, 1 Megaselia species and 1 was identified as Muscina stabulans.
Conclusions:
S. haemorrhoidalis was the commonest maggot involved. A high index of suspicion is required for clinical diagnosis when the patient complains of passing wriggling worms in faeces for a long period without any response to antihelminthics. The reason for long duration of illness and recurrence of infestation is baffling. The nearest to cure was colonic wash. We feel prevention is of utmost importance, which is to avoid eating food articles with easy access to flies.
Insights
Intestinal myiasis, a fly larvae infestation of the gastrointestinal tract, is often misdiagnosed. Early identification by clinical microbiologists is crucial to prevent incorrect treatments for this condition.
Area of Science:
- Medical Entomology
- Clinical Microbiology
- Parasitology
Background:
- Intestinal myiasis involves fly larvae inhabiting the human gastrointestinal tract.
- Ingestion of fly eggs or larvae on food leads to this infestation.
- Symptoms can range from mild to severe and are often mistaken for pinworm infections.
Purpose of the Study:
- To report on cases of intestinal myiasis.
- To highlight the importance of accurate diagnosis by clinical microbiologists.
- To differentiate intestinal myiasis from other parasitic infections like pinworm infestation.
Main Methods:
- Analysis of 7 cases of intestinal myiasis.
- Rearing larvae to adult flies in a modified meat and sand medium for identification.
- Utilizing a simple, laboratory-prepared rearing medium.
Main Results:
- Five of the seven identified larvae were Sarcophaga haemorrhoidalis.
- One larva was identified as Megaselia species.
- One larva was identified as Muscina stabulans.
Conclusions:
- Sarcophaga haemorrhoidalis is the most common fly species causing intestinal myiasis.
- A high index of suspicion is necessary for clinical diagnosis, especially when patients pass wriggling worms without response to antihelminthics.
- Prevention through avoiding food accessible to flies is paramount; the cause of prolonged illness and recurrence requires further investigation.
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