an anxiuous mother brought her 4yr old daughter to the pediatrician .the girl was passing loose stools past 20days .this was often associated with pain abdomen .stool examination showed the following organism :

Pathogenesis G. lamblia inhabits in the duodenum and upper ileum Trophozoites are attached to the mucosa surface by sucker, reproduced by binary fission Histology shoening of microvilli, elongation of crypts, and damaging the brush border of the absorptive cells Mechanical blockage of the intestinal mucosa, competition for nutrients, inflammation Diarrhea, abdominal pain, bloating, nausea, and vomiting CLINICAL MANIFESTATIONS incubation period :1-2 wk clinical manifestations :asymptomatic . acute infectious diarrhea, chronic diarrhea with failure to thrive and abdominal pain or cramping. Symptomatic infections occur more frequently in children than in adults. Most symptomatic patients : acute diarrhea. low-grade fever, nausea, and anorexia; intermittent or more protracted course characterized by diarrhea, abdominal distention and cramps, bloating, malaise, flatulence, nausea, anorexia, and weight loss develops treatment : metronidazole 200mg 7 days tid ref : ananathanaryana 9th ed