Gastroenteritis%20-%20parasitic Signs and Symptoms

• Parasites causing gastrointestinal symptoms may be transmitted to humans via the fecal-oral route by food or water ingestion, or by skin penetration

Parasites According to their Mode of Transmission

• Soil-transmitted helminths: Ascaris lumbricoides, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Trichuris trichiura
• Food-borne trematodes: Clonorchis sinensis, Opisthorchis viverrini, Fasciola hepatica, Paragonimus sp.
• Water-borne parasites: Schistosoma haematobium/japonicum/mansoni, Cryptosporidium sp., Giardia lamblia, Entamoeba histolytica

• Frequently, patients with gastrointestinal parasitic infections do not have any signs and symptoms that are specific for parasitic infections (eg fever, malaise, fatigue, sweating, weight loss, anorexia, edema, pruritus)
• Some patients may be asymptomatic
• Gastrointestinal symptoms, if present, include diarrhea, abdominal pain, dysentery, flatulence, jaundice, rectal prolapse, dyspepsia, malabsorption, vomiting and biliary colic
• Extraintestinal infection can also occur and may give rise to symptoms (eg headache, seizures, cough, dyspnea, hemoptysis, wheezing, vulvovaginitis, dysuria, hematuria, skin rashes, pruritus, arthralgia, anemia, fatigue and claudication)

Host Susceptibility Factors in Gastrointestinal Parasitic Infections

• Nutritional status
• Immunosuppressive drugs
• Age (newborn)
• Intercurrent disease
• Presence of a malignancy