Abstract:
Background: Cryptosporidiosis is an important cause of diarrheal illness, particularly in immunocompromised individuals. While it is commonly associated with HIV infection, it is increasingly recognized in patients receiving immunosuppressive therapies. Diagnosis is often challenging due to nonspecific clinical features and low sensitivity of routine stool examinations.
Case Presentation: A 52-year-old male from Eastern India with a history of Chronic Myeloid Leukemia on tyrosine kinase inhibitor therapy (initially Imatinib, later switched to Dasatinib due to molecular failure) presented with chronic diarrhea of one-month duration. The diarrhea was insidious in onset, occurring 4–5 times daily, mucoid, foul-smelling, and occasionally blood-streaked, and was associated with abdominal pain and intermittent fever. He also reported generalized pruritus and bilateral eye irritation. There was a history of recent swimming in a local water body.
On examination, he was hemodynamically stable with no significant systemic findings. Initial laboratory investigations, including HIV, hepatitis B and C serologies, were negative. Routine stool examination, culture, ova and cyst analysis, and testing for Clostridioides difficile infection were negative. Ultrasound abdomen was normal. Colonoscopy revealed rectal aphthous ulcers, and biopsy showed focal active colitis. Microbiological workup, including bacterial, fungal, and mycobacterial studies, was unremarkable.
Further evaluation with modified Ziehl–Neelsen staining of stool demonstrated acid-fast oocysts measuring 4–6 µm, suggestive of Cryptosporidiosis, which was confirmed by stool PCR detecting Cryptosporidium parvum.
Management and Outcome: The patient was treated with Nitazoxanide for 14 days with initial improvement. However, he developed recurrent symptoms at 3 months, requiring combination therapy with Azithromycin and nitazoxanide, resulting in temporary remission. At 9 months, recurrence occurred again, likely related to ongoing immunosuppression from dasatinib. Dose reduction of Dasatinib was undertaken in consultation with hematology, along with repeat nitazoxanide therapy. This led to sustained clinical and microbiological resolution at 6-month follow-up.
Conclusion: This case highlights disseminated cryptosporidiosis as an under-recognized cause of chronic diarrhea in non-HIV immunocompromised patients. A high index of suspicion, appropriate use of specialized diagnostic techniques such as modified acid-fast staining and PCR, and a combined approach of antimicrobial therapy with immune optimization are essential for successful management.
Biography:
Post-Doctoral Trainee in Infectious Diseases with strong clinical, academic, and research experience in managing complex infections, including immunocompromised hosts. Proven track record in national and international presentations, publications, and awards. Special interest in antimicrobial resistance, mycology, and emerging infections.
