Protozoan infections

Nitropyrimidin-2-amine, Enheptin-P (1046), is effective in suppressive and curative therapy of a common protozoan infection known as enterohepatitis or blackhead in turkeys (50MI21303). However, it seems that less expensive analogues, e.g. amnitrozole (2-acetamido-5-nitrothiazole), are preferred now. The subject is reviewed (58MI21302). 

Space constraints do not allow detailed discussions of the world of parasites, and clinicians and students are directed to some excellent resources for further details on parasites and parasitic diseases.1,2 Discussion in this chapter will include those parasitic diseases that are more likely to be seen in the United States and will include gastrointestinal parasites (primarily giardiasis and amebiasis), protozoan infections (malaria and South American trypanosomiasis), some common helminthic... 

Garg PK, Perry S, Dorn M, et al. Risk of intestinal helminth and protozoan infection in a refugee population. Am I Trop Med Hyg 2005 73 386-391. 

Antibiotic resistance Protozoan infection Benign prostate hyperplasia Cancer Cancer... 

It is worthwhile mentioning that treatment with high-dose (600 mg, 3 times a day, for 14 days) rifaximin was also efficacious in resolving the clinical symptoms and clearing protozoan infections in HIV-l-infected patients with a CD4 count >200/mm3, who presented enteric and sys-... 

Gorilla, Gorilla gorilla gorilla 35-year-old male at death in a Mexican zoo had various bacterial and protozoan infections and lead poisoning of unknown origin ... 

The most widespread protozoan infections caused by pathogenic protozoa are malaria, leishmaniasis, and trypanosoma, as well as trichomonas, amebiasis, giardia, and toxoplasmosis. All types of protozoa are single-cell organisms that can adapt to various conditions. They are much more versatile than bacteria. They have a fairly complex life cycle, and therefore they exist in many forms. These forms require different approaches when treating patients that have protozoan infections. Protozoa are typical parasites that occupy host cells, multiply in them, and then destroy them. 

In terms of mechanism of action and indications for use, tinidazole is very similar to metronidazole. It is also effective against amebas, trichomonad, lambliosis, acute ulcerative gingivitis, and post-operational anaerobic infections. It is used for treating practically all protozoan infections. Synonyms of this drug are tinaport, tinimed, and tinisan. 

Lambliosis, which is treated with quinicrine, is also considered a protozoan infection. In some cases, metronidazole and furazolidone are used for lambliosis. Metronidazole and tinidazole are used for treating trypchomonadiasis, another communicable protozoan infection. Sulfanilamides and chloridin are used for treating toxoplasmosis. 

Sulfonamides are used for controlling urinary tract infections, acute and chronic lung infections (norcadiosis), protozoan infections of the nervous system (i.e., toxoplasmosis), and a variety of infections in humans and livestock. Their mode of activity is by inhibiting the multiplication of bacteria by competitively inhibiting para-aminobenzioc acid (PABA) in the folic acid metabolism cycle (O Neil et al., 2001). More specifically, they block the synthesis of folic acid in bacteria as the drugs are structurally similar to PABA. Folic acid is essential to the synthesis of amino acids and nucleic acids. In bacteria, folic acid is synthesized from PABA... 

Pneumocystis carini pneumonia (PCP), the most common of the opportunistic infections, occurs in more than 80% of AIDS patients (13). Toxoplasmosis, a protozoan infection of the central nervous system, is activated in AIDS patients when the CD4+ count drops and severe impairment of cell-mediated immunity occurs. Typically, patients have a mass lesion(s) in the brain. These mass lesions usually respond well to therapy and can disappear completely. Fungal infections, such as Cyptococcalmeningitis, are extremely common in AIDS patients, and Histoplasma capsulatum appears when cell-mediated immunity has been destroyed by the HIV virus, leading to widespread infection of the lungs, liver, spleen, lymph nodes, and bone marrow. AIDS patients are particularly susceptible to bacteremia caused by nontyphoidal strains of Salmonella. Bacteremia may be cleared by using antibiotic therapy. 

Carlos Chagas discovered a new flagellated pathogenic protozoan species, and named it Trypanosoma (Schizotrypanzonum) crnzi. The symptoms caused by this protozoan infection were first described for marmoset (Callithrix penicillata). After that, Berenice, a 2-year-old girl, was the first case of what would be considered a new human disease (Kropf and Sa, 2009 Scliar, 2002 Voelker, 2009 WHO, 2009). 

Contraction of malaria, today known to be a protozoan infection caused by the bite of the Anopheles mosquito, does not accord immediate and/or universal immunity. Whereas those in geographical regions frequently exposed to malarial infection often exhibit no or attenuated symptoms, those less exposed can become severely and repeatedly ill. Even today the molecular mechanisms underlying natural immunity to malaria are not clearly understood. For details, see the Oxford Research on Childhood Disease Malaria at and WHO/TDR [World Health Organization/Tropical Disease Research] Database at (reviewed Feb. 6, 2001). Repeated attacks may even cause chronic malaria characterized by severe anemia, emaciation, enlargement of the spleen, weakness, edema of the ankles, and... 

A large number of parasitic protozoans infect cattle, horses, pigs, sheep, goats and birds causing a serious threat to the livestock health. The important protozoal diseases of domestic animals are described below. 

Immunology/infectious diseases Diseases affecting the defense mechanisms of the body. Studies in this area include AIDS, auto-immune diseases, bacterial infections, chronic fatigue syndrome, common cold, genital herpes, genital warts, hepatitis, HIV infections, immunosuppressive, influenza, lyme disease, meningitis, parasite and protozoan infections, strep throat, vaccines, viral infections, and others. 

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