Blastocystis hominis as a cause of chronic diarrhea in low-resource settings: A systematic review

Table 1 Characteristics of systematically reviewed studies

Ref.	Study design	Country	Population characteristics	Chronic diarrhea	Other symptoms	Treatment	Outcome
Andiran et al[27]	Case reports	Turkey	12-year male11-year male	Absent	Abdominal pain, anorexia, diarrhea, fever, Abdominal pain, diarrhea, fever, nausea, vomiting	MET and TMP/SMX (duration unknown) MET and TMP/SMX (duration unknown)	FR (time unknown) FR (time unknown)
Bhat Yellanthoor et al[40]	Case report	India	13-year male	Absent	Abdominal pain, bloody diarrhea, chills, diarrhea, fever, headache, rigors, vomiting	MET (duration unknown)	FR at 2 weeks
Dinleyici et al[28]	RCT	Turkey	48 children with symptoms > 2 weeks; randomized into three treatment groups: A (11 males; 7 females); B (8 males; 7 females); C (7 males; 8 females)	Unknown	Abdominal pain (31 patients), anorexia (6 patients), diarrhea (22 patients), flatulence, nausea/vomiting (8 patients)	A: Lyophilized Saccharomyces boulardii for 10 days (n = 18); B: MET for 10 days (n = 15); C: None (n = 15); MET after 2 weeks (n = 9)	77.7% (14/18) FR at 2 weeks; 94.4% (17/18) FR at 4 weeks; 66.6% (10/15) FR at 2 weeks; 73.3% (11/15) FR at 4 weeks; [72.7% (24/33) FR at 2 weeks (total treated); 84.4% (28/33) FR at 4 weeks (total treated)]; 40% (6/15) FR at 2 weeks
Fréalle et al[41]	Case report	Morocco	9-year female	Absent	Abdominal pain, anorexia, diarrhea, fever, vomiting, weakness (acute appendicitis)	Appendectomy, TIN, CEF, GEN for 10 days	FR at 2 weeks
Guirges and Al-Waili et al[37]	Prospective	Iraq	103 patients (54 males, 49 females) aged 8–65 years	Absent	Abdominal pain, diarrhea, flatulence	MET for 7 days	71.8% (74/103) FR at 1 week; 71.8% (74/103) FR at 4 weeks; no data for 29 patients
Hameed et al[32]	Case control prospective	Egypt	104 participants (54 cases aged 3–59 years; 50 controls aged 7–65 years); 20 symptomatic cases followed up	Absent	Abdominal pain, constipation, diarrhea, fatigue, fever, flatulence, vomiting, urticaria	MET for 5–10 days (n = 20)	60% (12/20) FR at 2 weeks; 100% (20/20) FR at 4 weeks
Kaya et al[29]	Prospective	Turkey	52 patients (22 males; 30 females) aged 3–61 years; 41 followed up	Absent	Abdominal distention, abdominal pain, constipation, diarrhea, perianal pruritus, urticaria, weight loss	MET for 2 weeks	92.3% (36/39) FR at 2 weeks for intestinal symptoms; 50% (1/2) FR at 2 weeks for extraintestinal symptoms except weight loss; 0% (0/1) FR at 2 weeks for weight loss
Lee et al[38]	Case report	Jamaica	29-year female	Absent	Abdominal pain, arthralgia, bloody diarrhea, diarrhea, fever, joint swelling, morning joint stiffness, vomiting	MET for 5–7 days	FR at 1 week
Moghaddam et al[36]	Prospective	Iran	104 patients (60 males; 44 females) aged 52 ± 16 years	Absent	Abdominal pain (102 patients), constipation (19 patients), diarrhea (72 patients), fever (13 patients), flatulence (27 patients)	MET and TMP/SMX for 10 days	73.6% (76/104) FR at 2 weeks; 18.9% (19/104) PR at 2 weeks; 1.9% (2/104) NR at 2 weeks
Ok et al[30]	Prospective	Turkey	53 patients (38 children aged 5–14 years; 15 adults aged 17–66 years)	Absent	Abdominal pain (52 patients), constipation (10 patients), diarrhea (37 patients), fever (7 patients), flatulence (14 patients)	TMP/SMX for 7 days	73.6% (39/53) FR at 1 week; 18.9% (10/53) PR at 1 week; 7.5% (4/53) NR at 1 week
Qadri et al[42]	Prospective	Saudi Arabia	239 patients (43 followed up after treatment)	Absent	Abdominal pain (210 patients), alternating diarrhea and constipation (35 patients), anorexia (13 patients), constipation (77 patients patients), depression (8 patients), diarrhea (56 patients), fatigue (25 patients), flatulence (4 patients), food intolerance (8), headache (9 patients), nausea (9 patients), vomiting (30 patients)	MET for 7–10 days	No data for up to 4 weeks
Rajamanikam et al[39]	Case reports	Malaysia	13-year male30-year male	Absent	Abdominal pain, weight loss Chronic flatulence, discomfort, exhaustion	MET for 10 days MET for 10 days	Worse at 2 weeks
Rajič et al[34]	Case report	Bosnia and Herzegovina	49-year male	Present	Chronic urticaria, angioedema	MET for 14 days	FR at 2 weeks
Rossignol et al[33]	RCT	Egypt	100 patients (37 males; 47 females) aged 2–43 years randomized into two treatment groups of 50 each	Absent	Abdominal pain (78 patients), anorexia (4 patients), bloody stool (6 patients), diarrhea, fever (12 patients), flatulence (7 patients), mucoid stool (12 patients), nausea (7 patients), vomiting (5 patients)	NIT for 3 days (n = 42), None (n = 42)	86% (36/42) FR at 1 week, 38% (16/42) FR at 1 week
Tai et al[35]	Prospective	China	6 patients (3 males; 3 females) with refractory ulcerative colitis aged 30–51 years	Present	Bloody stool, purulent stool	MET for 10–14 days	100% (6/6) PR at 2 weeks
Taşova et al[31]	Non-randomized trial	Turkey	206 adults with hematological malignancy (118 males; 88 females; 23 studied)200 adults without hematological malignancy (110 males; 90 females; 2 studied)	Absent	Abdominal pain, bloating, diarrhea, flatulence, nausea/vomiting	MET for 10 days (n = 23), No data	100% FR at 2 weeks, No data
Toro Monjaraz et al[40]	Retrospective	Mexico	138 patients (58 males; 80 females)	Absent	Functional abdominal pain	MET (36), ALB (1), MEB/TIN (34), NIT (9), RIF (1), SEC (18) or TMP/SMX (1) 37 not treated	68.3% (69/101) FR (time unknown). 35.1% (13/37) FR (time unknown)

ALB: Albendazole; CEF: Ceftriaxone; FR: Full recovery; GEN: Gentamicin; MEB: Mebendazole; MET: Metronidazole; NIT: Nitazoxanide; NR: No recovery; PR: Partial recovery; RCT: Randomized controlled trial; RIF: Rifaximin; SEC: Secnidazole; TIN: Tinidazole; TMP/SMX: Trimethoprim/sulfamethoxazole.