Introduction
Pathogenicity
Patient | Clinical history | Diagnosis | Treatment | Outcome | Study |
---|---|---|---|---|---|
One 11 y.o male and one 12 y.o male | Both presented with right lower quadrant tenderness, anorexia, abdominal pain, nausea, vomiting | Initially diagnosed with appendicitis. Stool examination showed Blastocystis and patients were then diagnosed with Blastocystis infection | Metronidazole and co-trimoxazole | Complete recovery | [15] |
24 y.o female | Nine week history of urticaria, hives, chronic diarrhoea, IBS | Initially diagnosed with cellulitis. Treated with non-steroidal cream with no recovery of symptoms. Presented with hives and diagnosed as urticaria. Extensive investigation showed 4 + Blastocystis in her stool. | Metronidazole | All urticarial and IBS symptoms cleared | [24] |
45 y.o female | Four month history of erythematous and pruriginous lesions on trunk and limbs, mild gastoenteric complaints | Diagnosed with urticaria. Extensive investigation showed the stool postive for Blastoycstis. | Paromomycin and metronidazole | All urticarial and gastrointestinal symproms cleared | [25] |
32 y.o female | Four year history of allegic rhinitis and chronic urticaria, swelling in pressure sites | Diagnosed with delayed pressure urticaria. Treated with systemic corticosteroids with only partial clearance of symptoms. Stool examination positive for Blastocystis | Metronidazole | All urticarial symptoms cleared | [26] |
60 y.o female | Four year history of anaphylactoid reactions, severe asthma and generalised urticaria | Diagnosed with chronic urticaria. Extensive investigation identified Blastocystis in the stool | Paromomycin | All urticaria symptoms cleared | [27] |
74 y.o male | Diarrhoea, abdominal pain, nausea, fatigue and fever | Hospitalised. Stool were positive for Blastocystis | Metronidazole | Clearence of symptoms after 10days | [18] |
29 y.o female | Six month history of morning stiffness, pain and swelling of joints, elbows, ankles, knees, diarrhoea, abdominal pain and vomiting | Treated for presumed infectious arthritis of the knee. No improvement. Microscopy of the synovial fluid and stools both showed the presence of Blastocystis. | Metronidazole | After two weeks knee inflammation subsided and all abdominal pain and diarrhoea were cleared | [28] |
24 y.o male | Six week history of diffuse abdominal pain and diarrhoea | Stool examination was positive for Blastocystis and Endolimax nana. | Metronidazole | Complete resolution of symptoms 10days later | [29] |
19 y.o male | Three week history of hives, abdominal pain for 2.5months | Diagnosed with acute urticaria. Routine testing showed the presence of Blastocystis in the stool ST3 | Metronidazole | 10days after treatment both urticaria and abdominal discomfort were cleared | [21] |
20 y.o male | Urticaria and flatulence | Treated with antihistamines with no success. Further investigation showed Blastocystis ST2 in the stool. Initially treated with metronidazole but treatment failure appears to have occured. Then treated with co-trimoxazole with no success and finally treated with combination metronidazole and paramomycin | Metronidazole then co-trimoxazole followed by paromomycin | All symptoms cleared 10 days later | [22] |
40 y.o female | Hospitalised due to severe diarrhoea and fever | Blastocystis ST8 infection diagnosed from stool cultures. Treated with metronidazole. Symptoms persisted and the patient also noted bloating, flatulence and abdominal pain. Further treated with co-trimoxazole | Metronidazole then co-trimoxazole | All symptoms cleared | [30] |
Immune response and animal studies
Blastocystis infection in immunodeficient patients
Irritable bowel syndrome and the role of Blastocystis
Treatment
Treatment (Dose) | Efficacy | Reference |
---|---|---|
Iodoquinole (650 mg t.i.d) | 0% | [91] |
Emetine (100 μg/ml) | 50% | [92] |
Metronidazole (2000 mg s.i.d) | 0% | [93] |
Metronidazole (1500 mg s.i.d) | 100% | [26] |
Metronidazole (750 mg t.i.d) | 100% | [24] |
Metronidazole (750 mg t.i.d) | 100% | [21] |
Metronidazole (500 mg t.i.d) | 100% | [79] |
Metronidazole (250- 750 mg t.i.d) | 33% | [80] |
Metronidazole (750 mg t.i.d) | 100% | [81] |
Metronidazole (1500 mg s.i.d) | 80% | [94] |
Metronidazole (800 mg t.i.d) | 0% | [30] |
Metronidazole (30 mg/kg twice daily) | 67% | [89] |
Nitazoxanide (500 mg t.i.d) | 100% | [86] |
Nitazoxanide (100-200 mg b.i.d for children <12 yr, 500 mg b.i.d for >11 yr) | 86% | [88] |
Nitazoxanide (500 mg t.i.d) | 100% | [95] |
Ornidazole (500 mg t.i.d) | 50% | [96] |
Paromomycin (25 mg/kg t.i.d) | 100% | [93] |
Paromomycin (500 mg t.i.d) | 100% | [97] |
Paromomycin (25 mg/kg t.i.d) | 100% | [82] |
Paromomycin (1000 mg b.i.d) & MZ (750 mg t.i.d) | 100% | [25] |
Saccharomyces boulardii (250 mg b.i.d) | 78% | [89] |
Trimethroprim-SMX | 22% | [80] |
Trimethroprim-SMX (6 mg/kg TMP, 30 mg/kg SMX s.i.d) | 95% | [98] |
Trimethropim- SMX (320 mg TMP, 1600 mg SMX s.i.d) | 93% | [98] |
Trimethroprim- SMX (80 mg TMP, 400 mg SMX t.i.d) | 100% | [30] |
Triple therapy (nitazoxanide, furazolidone and secnidazole) | 0% | [90] |