Treating T. Foetus Diarrhea in Cats
Tritrichomonas foetus typically affects cattle as a venereal pathogen. Recently, it has been recognized as a
pathogen that causes colitis in domestic cats.The infection is most likely spread by the fecal-oral route. Dense
housing is a risk factor, and the infection has become widespread in catteries. In a study of 117 cats from 89
catteries at an international cat show, T. foetus was found in 36 cats representing 28 catteries. No effective
treatment has been found. Some cats have persistent diarrhea for up to 2 years, and some may remain
infected for life.The authors of this article tested ronidazole (RDZ), tinidazole, and metronidazole against the
parasite in vitro and RDZ alone for the treatment of naturally occurring disease and experimentally induced
infections.The one case of naturally occurring disease
was found in a 3-year-old, spayed female Persian cat that
since 6 months of age had unrelenting large bowel diar-
rhea. Infection with T. foetus had been confirmed by
direct microscopy, microbial culture for trichomonads,
and single-tube nested PCR testing.The cat had been
treated with a variety of antimicrobials. It was given 10
mg/kg RDZ by mouth daily for 10 days.Within 24 hours
of initiation of treatment, trichomonads were no longer
visible by direct examination of the feces. Fecal consis-
tency improved dramatically. Feces remained formed and
tested negative for T. foetus infection by culture and
polymerase chain reaction assay on days 15 and 31. On
day 85, there was an acute onset of large bowel diarrhea
with blood and mucus. Another 10 days of treatment
with RDZ was initiated. Immediate resolution of diarrhea
and fecal shedding of the trichomonads was observed.The cat tested negative on days 22, 37, and 407.The
findings suggest that RDZ at 30 to 50 mg/kg twice a day by mouth resulted in long-term elimination of T.foetus infection and diarrhea. Periods between relapse were often prolonged. COMMENTARY: Chronic large bowel diarrhea in cats can be one of the most frustrating challenges in veteri-
nary gastroenterology. Known causes include dietary sensitivity; inflammatory bowel disease; colonic lym-
phosarcoma and other tumors; and infection with Salmonella species, Clostridium species, and possibly
Campylobacter species. Other bacteria and chronic viral infections (FIV, FIP, and FeLV) can also be associated
with large bowel signs. Parasite infection, including Ancylostoma and Giardia (yes, they can cause large bowel
signs) and Cryptosporidium species, should also be considered. Infection with T. foetus has emerged as an
important and arguably one of the most frustrating causes of chronic diarrhea in cats because of difficulties
inherent in diagnosis and lack of effective treatment. T. foetus is a flagellated protozoan parasite that resides
in the colon of domestic cats and causes colitis and chronic, foul-smelling diarrhea. Ronidazole is related to
metronidazole and is effective in eliminating the organism and resolving diarrhea at a dose of 30 to 50
mg/kg PO Q 12 H for 14 days.The drug is not currently licensed for human or veterinary use, but the chemical
grade compound is available from Sigma.—Colin F. Burrows, BVetMed, PhD, MRCVS, Diplomate ACVIM
Efficacy of ronidazole for treatment of feline Tritrichomonas foetus infection. Gooking JL, Copple CN, Papich MG, et al. J VET INTERN MED 20:536-543, 2006. Feline trichomoniasis: An emerging disease? Stockdale HD, Spencer JA, Dystra CC, et al.COMPEND CONTIN EDUC PRACT VET 28:463-471, 2006.
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R e v i e w s / C o m m e n t a r i e s / A D A S t a t e m e n t s P E R S P E C T I V E S Aspects of Insulin Treatment ZACHARY T. BLOOMGARDEN, MD system and a separate electronic controller,smaller than traditional pumps and with alarge insulin reservoir. Medtronic also may T hisisthesecondofaseriesofarticles periodsoflesserandgreaterinsulinsen- be developing a patch delivery system
Department of Justice GlaxoSmithKline to Plead Guilty & Pay $750 Million to Resolve Criminal and Civil Liability Regarding Manufacturing Deficiencies at Puerto Rico Plant BOSTON – SB Pharmco Puerto Rico Inc., a subsidiary of GlaxoSmithKline, PLC (GSK), has agreed to plead guilty to charges relating to the manufacture and distribution of certain a