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Intestinal Protozoal Diseases: Treatment & Medication
Updated: Nov 13, 2009
- Overview
- Differential Diagnoses & Workup
- Treatment & Medication
- Follow-up
- Multimedia
Treatment
Medical Care
- The most important aspect of providing care for children with diarrhea caused by intestinal protozoa includes standard pediatric assessments.
- Evaluate the child for signs of dehydration, including tachycardia, delayed capillary refill, decreased tears, decreased activity, decreased urine output, and altered mental status.
- Hypovolemic shock rarely occurs with these infections but must be recognized.
- The child must be evaluated for the adequacy of the nutritional status. This is particularly important in cases of chronic diarrhea and possible immunodeficiency.
- Weight must be measured and compared on the growth curve. Appropriate interventions occur following this immediate assessment.
- Oral rehydration therapy (ORT) is the preferred approach for children with mild-to-moderate dehydration. Intravenous rehydration should rarely be necessary. Current recommendations for pediatric rehydration are outlined best in The Management of Acute Diarrhea in Children: Oral Rehydration, Maintenance, and Nutritional Therapy.19
- Following immediate fluid resuscitation for dehydration, the clinician must address potential nutritional issues and provide adequate nutrition to the child with acute or chronic diarrhea.
- Protozoal GI infections in immunocompetent patients are usually mild-to-moderate self-limited diseases, and special precautions are not needed.
- The hallmark for treatment of these diseases is specific antiprotozoal therapy.
- Patients with severe amebic or balantidic colitis should not receive oral nutrition and should be monitored for potential surgical complications.
- Consider parenteral nutrition in some patients.
- Patients with amebic liver abscess should be treated in the hospital until potential complications have been ruled out.
Surgical Care
Only 2 well-recognized conditions in which surgical therapy is necessary for intestinal protozoal diseases are known: necrotizing colitis, caused by E histolytica or B coli, and complicated amebic liver abscess.
- Indications for surgery in fulminant amebic colitis include the following:
- Failure to respond to antiamebic drugs following perforation and localized abscess formation
- Persistence of abdominal distension and tenderness despite effective antiamebic therapy
- Toxic megacolon
- Partial colectomy with colostomy is recommended over primary anastomosis for localized colonic disease because an anastomosis may be incompetent because of the friable condition of the affected intestinal wall.
- For extensive disease, better surgical results have been obtained with total colectomy with exteriorization of the proximal and distal ends.
- Indications for needle aspiration in amebic liver abscess include the following:
- Rupture to pleura, pericardium, or both
- Left lobe abscesses and proximity to the pericardium
- As a diagnostic procedure when a pyogenic abscess is highly suspected
- When surgical drainage is indicated because of imminent rupture of the abscess to the peritoneal cavity or presence of necrotizing colitis
- When, in some cases, perianal fistulization of intestinal amebic foci is present and necessitates surgical drainage
Consultations
- The primary care physician can manage the vast majority of cases of gastroenteritis associated with protozoal infections. These infections rarely result in complications requiring hospitalization.
- In patients with chronic diarrhea or amebic liver abscess, consultation with a gastroenterologist along with an infectious-disease specialist may be useful.
- Surgeons should be consulted when the patient is suspected to have necrotizing colitis, complicated amebic liver abscess, or both.
- Nutritional support may also be beneficial in severe cases.
Diet
- In immunocompetent patients, effective antiprotozoal therapy results in full recovery.
- Some patients with severe giardiasis may experience disaccharidase deficiency and may require lactose-free diets, but this is a temporary condition that usually does not last more than 2 weeks.
- Patients with AIDS and severe spore-forming protozoal infections (chronic diarrhea with wasting syndrome) require hypercaloric diets. This is indicated for the protozoal illness in addition to the wasting syndrome associated with the underlying disease.
- For amebic liver abscess, some experts recommend a low-fat diet during antiamebic treatment, but no clinical trials have examined the effects of this diet on the patient's outcome.
Activity
- The only limitations for physical activity are in patients with amebic liver abscess who may require hospitalization and patients who require surgery for necrotizing colitis.
Medication
The drugs of choice for each protozoon are listed in Table 3 and are followed by specific considerations for each drug.
Table 3. Specific Therapy for Intestinal Protozoal Infections
Open table in new window
Table
| Organism | Drugs, Pediatric Dose, and Treatment Duration |
| E histolytica (Luminal disease or colonization) | Iodoquinol: 40 mg/kg/d PO divided tid for 20 d; not to exceed 2 g/d |
| Paromomycin: 25-30 mg/kg/d PO divided tid for 7 d | |
| E histolytica (Moderate colitis) | Metronidazole: 50 mg/kg/d PO divided tid for 10 d |
| Tinidazole: 50 mg/kg/d PO for 3 d; not to exceed 2 g/d | |
| E histolytica (Severe colitis or liver abscess) | Metronidazole: 50 mg/kg/d PO divided tid for 10 d |
| Dehydroemetine*: 1-1.5 mg/kg/d divided bid PO for 5 d | |
| Tinidazole†: 50 mg/kg/d PO for 3-5 d; not to exceed 2 g/d | |
| G lamblia | Metronidazole: 15-20 mg/kg/d PO divided tid for 5 |
| Tinidazole: 50 mg/kg/d PO once; not to exceed 2 g/dose | |
| Quinacrine‡: 6 mg/kg/d PO divided tid for 5 d; not to exceed 300 mg/d | |
| Furazolidone: 6 mg/kg/d PO divided qid for 7-10 d | |
| Paromomycin: 40 mg/kg/d PO divided tid for 7 d | |
| Nitazoxanide: 200-400 mg/d PO divided bid for 3 d | |
| D fragilis | Iodoquinol: 50 mg/kg/d PO divided tid for 20 d; not to exceed 2 g/d |
| Paromomycin: 30 mg/kg/d PO divided tid for 7 d | |
| Tetracycline: 40 mg/kg/d PO divided qid for 10 d; not to exceed 2 g/d | |
| C parvum§ | Paromomycin*: 30 mg/kg/d PO divided tid (duration unknown) |
| Nitazoxanide: 200-400 mg/d PO divided bid for 3 d | |
| I belli | Trimethoprim/sulfamethoxazole (TMP/SMZ): 20/100 mg/kg/d PO divided bid for 10 d, followed by 10/50 mg/kg/d PO divided bid for 21 d |
| C cayetanensis | TMP/SMZ: 10/50 mg/kg/d PO divided bid for 3 d |
| Microsporidia S intestinalis | Albendazole* (adult dose): 800 mg/d PO divided bid |
| Microsporidia E bieneusi | No treatment recommended; albendazole may decrease the number of organisms |
| B coli | Tetracycline: 40 mg/kg/d PO divided qid for 10 d; not to exceed 2 g/d |
| Metronidazole: 35-50 mg/kg/d PO divided tid for 5 d | |
| Iodoquinol: 40 mg/kg/d PO divided tid for 20 d | |
| B hominis | Metronidazole: 35-50 mg/kg/d PO divided tid for 10 d |
| Iodoquinol: 40 mg/kg/d PO divided tid for 20 d | |
| Nitazoxanide||: 500 mg/d PO divided bid for 3 d |
| Organism | Drugs, Pediatric Dose, and Treatment Duration |
| E histolytica (Luminal disease or colonization) | Iodoquinol: 40 mg/kg/d PO divided tid for 20 d; not to exceed 2 g/d |
| Paromomycin: 25-30 mg/kg/d PO divided tid for 7 d | |
| E histolytica (Moderate colitis) | Metronidazole: 50 mg/kg/d PO divided tid for 10 d |
| Tinidazole: 50 mg/kg/d PO for 3 d; not to exceed 2 g/d | |
| E histolytica (Severe colitis or liver abscess) | Metronidazole: 50 mg/kg/d PO divided tid for 10 d |
| Dehydroemetine*: 1-1.5 mg/kg/d divided bid PO for 5 d | |
| Tinidazole†: 50 mg/kg/d PO for 3-5 d; not to exceed 2 g/d | |
| G lamblia | Metronidazole: 15-20 mg/kg/d PO divided tid for 5 |
| Tinidazole: 50 mg/kg/d PO once; not to exceed 2 g/dose | |
| Quinacrine‡: 6 mg/kg/d PO divided tid for 5 d; not to exceed 300 mg/d | |
| Furazolidone: 6 mg/kg/d PO divided qid for 7-10 d | |
| Paromomycin: 40 mg/kg/d PO divided tid for 7 d | |
| Nitazoxanide: 200-400 mg/d PO divided bid for 3 d | |
| D fragilis | Iodoquinol: 50 mg/kg/d PO divided tid for 20 d; not to exceed 2 g/d |
| Paromomycin: 30 mg/kg/d PO divided tid for 7 d | |
| Tetracycline: 40 mg/kg/d PO divided qid for 10 d; not to exceed 2 g/d | |
| C parvum§ | Paromomycin*: 30 mg/kg/d PO divided tid (duration unknown) |
| Nitazoxanide: 200-400 mg/d PO divided bid for 3 d | |
| I belli | Trimethoprim/sulfamethoxazole (TMP/SMZ): 20/100 mg/kg/d PO divided bid for 10 d, followed by 10/50 mg/kg/d PO divided bid for 21 d |
| C cayetanensis | TMP/SMZ: 10/50 mg/kg/d PO divided bid for 3 d |
| Microsporidia S intestinalis | Albendazole* (adult dose): 800 mg/d PO divided bid |
| Microsporidia E bieneusi | No treatment recommended; albendazole may decrease the number of organisms |
| B coli | Tetracycline: 40 mg/kg/d PO divided qid for 10 d; not to exceed 2 g/d |
| Metronidazole: 35-50 mg/kg/d PO divided tid for 5 d | |
| Iodoquinol: 40 mg/kg/d PO divided tid for 20 d | |
| B hominis | Metronidazole: 35-50 mg/kg/d PO divided tid for 10 d |
| Iodoquinol: 40 mg/kg/d PO divided tid for 20 d | |
| Nitazoxanide||: 500 mg/d PO divided bid for 3 d |
*Efficacy is unknown.
†Drug is available from the CDC Drug Service (phone: 404-639-3670; evenings, weekends, and holidays: 404-639-2888).
‡ Drug is not available in the United States.
§Recommended regimens are indicated only in patients who are immunosuppressed. A recent meta-analysis has not shown evidence for a reduction in the duration or frequency of diarrhea by nitazoxanide or paromomycin when compared with placebo in immunosuppressed patients, nevertheless, oocyst clearance was significantly reduced.20
||Recent studies have shown effective outcomes when compared to placebo, but no clinical trials have compared with other antiparasitic drugs.
Antiprotozoal agents
Protozoal infections occur throughout the world and are a major cause of morbidity and mortality in some regions. Immunocompromised patients are especially at risk. Primary immune deficiency is rare, whereas secondary deficiency is more common. Immunosuppressive therapy, cancer and its treatment, HIV infection, and splenectomy can all increase vulnerability to infection. Infectious risk is proportional to neutropenia duration and severity. Protozoal infections are typically more severe in immunocompromised patients than in immunocompetent patients. In the case of cryptosporidiosis, nitazoxanide has been shown to be effective in immunocompetent and probably in immunocompromised patients, and the role of HAART has significantly reduced the incidence of all spore-forming protozoal infections.
Iodoquinol (Yodoxin)
Used for infections caused by E histolytica, B coli, B hominis, and D fragilis. Iodoquinol, also known as diiodohydroxyquin, is a halogenated quinoline.
Adult
650 mg PO tid pc; not to exceed 2 g/d
Pediatric
40 mg/kg/d PO divided tid
None reported
Documented hypersensitivity, iodine intolerance; hepatic or renal dysfunction
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Rarely causes nausea, abdominal cramps, rash, acne, and enlargement of thyroid gland; use with caution in patients with thyroid disease; protein-bound serum iodine levels may increase during treatment with iodoquinol, interfering with certain thyroid function tests
Metronidazole (Flagyl)
Used for infections caused by E histolytica, B coli, B hominis, and G lamblia. Metronidazole is a nitroimidazole.
Adult
E histolytica or B coli: 500-750 mg PO/IV tid
G lamblia: 250 mg PO/IV tid; not to exceed 2250 mg/d
Pediatric
E histolytica or B coli: 35-50 mg/kg/d PO/IV divided tid
G lamblia: 15 mg/kg/d PO/IV divided tid
May produce a disulfiramlike reaction with alcohol; an acute toxic psychosis may occur with disulfiram; increases anticoagulant effect of PO anticoagulants; phenobarbital and hydantoins increase metabolism of metronidazole and decrease its effects
Documented hypersensitivity; patients with organic neurologic disorders
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
Do not use in first trimester of pregnancy; nausea, headache, metallic taste, diarrhea, vomiting, and, less frequently, insomnia, stomatitis, vertigo, paresthesia, dark urine, and dry mouth are adverse effects; adjust dose in hepatic disease; monitor for seizures and development of peripheral neuropathy
Paromomycin (Humatin)
Used for infections caused by E histolytica, G lamblia, D fragilis, and C parvum. It is a nonabsorbable oral aminoglycoside.
Adult
500-750 mg PO tid; not to exceed 3 g/d
Pediatric
30 mg/kg/d PO divided tid
None reported
Documented hypersensitivity; intestinal obstruction
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Adverse effects (usually with doses >3 g/d) are diarrhea, abdominal pain, and, more rarely, dizziness and nausea; in patients with concomitant inflammatory bowel disease, the drug can be absorbed and result in ototoxicity/nephrotoxicity; because of narrow therapeutic index and toxic hazards associated with extended administration, do not use for long-term therapy; caution in renal failure (adjust dose), hypocalcemia, myasthenia gravis, and conditions that depress neuromuscular transmission
Tetracycline (Sumycin)
Used for infections caused by B coli and D fragilis. It is a broad-spectrum antibiotic.
Adult
1-2 g/d PO divided qid; not to exceed 2 g/d
Pediatric
<8 years: Not recommended
>8 years: 40 mg/kg/d PO divided qid; not to exceed 2 g/d
Increases toxicity of digoxin; increases effects of insulin; sucralfate decreases absorption of tetracycline (should be administered in intervals >2 h); increases toxicity of methoxyflurane, avoid concurrent use
Documented hypersensitivity; severe hepatic dysfunction
Pregnancy
D - Fetal risk shown in humans; use only if benefits outweigh risk to fetus
Precautions
Increases toxicity of digoxin; increases effects of insulin; sucralfate decreases absorption of tetracycline (should be administered in intervals >2 h); increases toxicity of methoxyflurane, avoid concurrent use; bioavailability decreases with antacids containing aluminum, calcium, magnesium, iron, or bismuth subsalicylate; can decrease effects of PO contraceptives, causing breakthrough bleeding and increased risk of pregnancy
Trimethoprim/sulfamethoxazole (TMP/SMZ, Bactrim, Septra)
Used for infections caused by C cayetanensis and I belli. It is a broad-spectrum antibacterial and antiprotozoal antibiotic. Considered DOC for isosporiasis and cyclosporiasis.
Adult
TMP/SMZ: 80/400-160/800 mg PO bid; not to exceed 320 mg/d TMP, 1600 mg/d SMZ
Pediatric
TMP/SMZ: 10/50 mg/kg/d PO divided bid
Azathioprine, reports of leukopenia; decreases effects of oral contraceptives; decreases levels of cyclosporin A; increases levels of loperamide; increases levels of methotrexate; increases levels of rifampin and phenytoin; increases activity of warfarin; coadministration with dapsone may increase blood levels of both drugs; coadministration of diuretics increases incidence of thrombocytopenia purpura in elderly persons; phenytoin levels may increase with coadministration; may potentiate effects of methotrexate in bone marrow depression; hypoglycemic response to sulfonylureas may increase with coadministration; may increase levels of zidovudine
Documented hypersensitivity; megaloblastic anemia caused by folate deficiency; age <2 years
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Do not use in pregnancy near term; adverse effects are rash (common in patients with AIDS), photosensitivity, and nausea; very rarely, exfoliative dermatitis, Stevens-Johnson dermatitis, and aplastic anemia may occur; discontinue at first appearance of rash or sign of adverse reaction; obtain CBC counts frequently; discontinue therapy if significant hematologic changes occur; goiter, diuresis, and hypoglycemia may occur with sulfonamides; prolonged IV infusions or high doses may cause bone marrow depression (if signs occur, give 5-15 mg/d leucovorin); caution in folate deficiency (eg, individuals with chronic alcoholism, elderly persons, those receiving anticonvulsant therapy, or patients with malabsorption syndrome); hemolysis may occur in G-6-PD deficiency; patients with AIDS may not tolerate or respond to TMP/SMZ; caution in renal or hepatic impairment (perform urinalyses and renal function tests during therapy); give fluids to prevent crystalluria and stone formation
Dehydroemetine (Mebadin)
Not FDA-approved in the United States. Used for infections caused by E histolytica. It is a main alkaloid of ipecac, less toxic than emetine; used only in combination with other drugs against severe forms of invasive amebiasis. Available in US only from the Parasitic Disease Drug Service, CDC (Atlanta, GA 30333; telephone: 404-639-3670). For more information, see CDC Drug Service.
Adult
1 mg/kg/d IM divided bid; not to exceed 90 mg/d
Pediatric
1-1.5 mg/kg/d IM divided bid
None reported
Documented hypersensitivity; cardiac disease; renal disease; recent history of polyneuritis
Pregnancy
X - Contraindicated; benefit does not outweigh risk
Precautions
Adverse effects include nausea, vomiting, diarrhea, ECG changes, cardiac arrhythmias, precordial pain, paresthesias, and weakness; avoid strenuous exercise for up to 4 wk after treatment; careful monitoring required during administration; ECG required before and after treatment (day 5 and day 10, then qwk for 2 wk); discontinue if resting pulse >110/min, marked hypotension, precordial pain, marked neuromuscular symptoms, T-wave depression, arrhythmias, or proteinuria occur
Furazolidone (Furoxone)
Used for infections caused by G lamblia; it is an oxazolidine and belongs to the group of the nitrofurans.
Adult
400 mg/d PO divided qid; not to exceed 400 mg/d
Pediatric
<1 month: Contraindicated; increases risk of hemolytic anemia
>1 month: 6 mg/kg/d PO divided qid
Increases effects of sedatives, antihistamines, and narcotics; disulfiramlike reaction with ethanol; increase risk of hypertensive crisis with sympathomimetic amines or MAOIs; avoid tyramine-containing foods, such as broad beans, yeast extracts, strong pasteurized cheese, beer, wine, chicken livers, and fermented products; increases levodopa blood concentrations and, thus, potential for toxicity; increases toxicity of paroxetine, fluoxetine, sertraline, trazodone, and tricyclic antidepressants
Documented hypersensitivity; age <1 mo
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Adverse effects are nausea, vomiting, headache, malaise; rarely associated with hypotension, urticaria, arthralgia, rash, hemolytic anemia; caution in G-6-PD deficiency when administering prolonged treatments; medication inhibits enzyme monoamine oxidase
Quinacrine (Atabrine)
Used for infections caused by G lamblia. It is an acridine derivative.
Adult
300 mg/d PO divided tid; not to exceed 300 mg/d
Pediatric
6 mg/kg/d PO divided tid
Increases toxicity of primaquine; increased risk of blood dyscrasias with aurothioglucose; may cause hypertension when coadministered with sympathomimetic amines, MAOIs, tyramine-containing foods or TCAs
Documented hypersensitivity; porphyria, psoriasis; history of psychosis
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Adverse effects are dizziness, headache, vomiting, and, very rarely, toxic psychosis, blood dyscrasia, urticaria, exfoliative dermatitis, yellow staining of skin and sclera, and blue and black nail pigmentation; caution in G-6-PD deficiency or seizure disorders
Albendazole (Albenza)
Used for infections caused by E bieneusi. It is an imidazole derivative, mostly used for helminths. Its efficacy against microsporidia is still unknown.
Adult
800 mg/d PO divided bid; not to exceed 800 mg/d
Pediatric
Not established
Coadministration with carbamazepine may decrease efficacy; dexamethasone, cimetidine, and praziquantel may increase toxicity
Documented hypersensitivity
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
Precautions
Caution in liver and hematologic diseases; discontinue use if LFTs increase significantly (resume when levels decrease to pretest values); abdominal pain, nausea, vomiting, diarrhea, dizziness, vertigo, fever, increased intracranial pressure, and alopecia may occur
Tinidazole (Fasigyn, Tindamax)
Nitroimidazole, similar to metronidazole. It is used for infections caused by E histolytica and G lamblia.
Adult
Intestinal amebiasis: 2 g PO qd for 3 d with food
Hepatic amebic abscess: 2 g PO qd for 3-5 d with food
Giardiasis: 2 g PO once with food
Pediatric
<3 years: Not established
>3 years:
Giardiasis: 50 mg/kg PO once with food; not to exceed 2 g/dose
Intestinal amebiasis: 50 mg/kg/d PO for 3 d with food; not to exceed 2 g/dose
Amebic liver abscess: 50 mg/kg/d PO for 3-5 d with food; not to exceed 2 g/dose, limited data exist for pediatric patients treated >3 d (monitor closely)
Limited data exist; interaction information based on experience with other nitroimidazole derivatives (ie, metronidazole); may prolong PT when coadministered with warfarin; avoid alcoholic beverages and preparations containing ethanol or propylene glycol during and 3 d following administration (may cause disulfiramlike reaction); may increase serum levels of lithium, phenytoin, cyclosporine, tacrolimus, and fluorouracil; CYP450 inducers (eg, phenobarbital, rifampin, phenytoin) may increase elimination; CYP450 inhibitors (eg, cimetidine, ketoconazole) may decrease elimination; concurrent administration with cholestyramine may decrease PO bioavailability; oxytetracycline may antagonize effect
Documented hypersensitivity; first trimester of pregnancy
Pregnancy
C - Fetal risk revealed in studies in animals but not established or not studied in humans; may use if benefits outweigh risk to fetus
X - Contraindicated; benefit does not outweigh risk
Precautions
Pregnancy category X during first trimester; carcinogenicity has been observed in mice and rats treated chronically with metronidazole (another nitroimidazole), although not observed with tinidazole, use cautiously; seizures and peripheral neuropathy have been reported; caution with history of blood dyscrasia; may cause metallic/bitter taste, nausea, anorexia, vomiting, weakness, fatigue, dizziness, or headache; if administered on day of hemodialysis, administer additional dose equivalent to half of recommended dose following dialysis
Nitazoxanide (Alinia)
Inhibits growth of C parvum sporozoites and oocysts and G lamblia trophozoites. Elicits antiprotozoal activity by interfering with pyruvate-ferredoxin oxidoreductase (PFOR) enzyme-dependent electron transfer reaction, which is essential to anaerobic energy metabolism. Available as a 20-mg/mL oral susp.
Adult
500 mg PO bid for 3 d
Pediatric
<1 year: Not established
1-3 years: 100 mg (5 mL) PO q12h for 3 d with food
4-11 years: 200 mg (10 mL) PO q12h for 3 d with food
>11 years: Administer as in adults
Tizoxanide (nitazoxanide metabolite) is >99.9% bound to plasma protein and may potentially displace other highly plasma protein-bound drugs resulting in increased toxicity
Documented hypersensitivity
Pregnancy
B - Fetal risk not confirmed in studies in humans but has been shown in some studies in animals
Precautions
May cause abdominal pain, diarrhea, vomiting, or headache; administer with food; caution when coadministered with other highly plasma protein-bound drugs with narrow therapeutic indices
More on Intestinal Protozoal Diseases |
| Overview: Intestinal Protozoal Diseases |
| Differential Diagnoses & Workup: Intestinal Protozoal Diseases |
 Treatment & Medication: Intestinal Protozoal Diseases |
| Follow-up: Intestinal Protozoal Diseases |
| Multimedia: Intestinal Protozoal Diseases |
| References |
| « Previous Page | Next Page » |
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Further Reading
Keywords
intestinal protozoal diseases, protozoal gastroenteritis, spore-forming protozoa, amebiasis, giardiasis, dientamoebiasis, balantidiasis, blastocystosis, treatment, diagnosis
