Heterophyes Heterophyes and other trematode infections - PDF

Distribution: Egypt (Nile Delta around Borolos and Manzala lakes), Middle East, Far East Habitat: Small intestine, embedded between villi. DH: Man, and fish-eating animals (dogs and cats). IH: It requires two IH 1st: Brackish water snail Pirenella conica (Amplifier host)...

Distribution: Egypt (Nile Delta around Borolos and Manzala lakes), Middle East, Far East Habitat: Small intestine, embedded between villi. DH: Man, and fish-eating animals (dogs and cats). IH: It requires two IH 1st: Brackish water snail Pirenella conica (Amplifier host) 2nd: Tilapia (Bolty) and Mugil (Boury) fish (Transport hosts) RH: Dogs and cats. Morphology Pear-shaped, unsegmented, 1-1.7 mm, it has three suckers: oral, ventral and genital, simple intestinal caeca, one spherical ovary and 2 oval testes beside each other in the posterior part. Vit. glands on both sides of post. half. Heterophyes adult embedded in intestinal mucosa Life Cycle of Heterophyes heterophyes Mode of infection lophocercous cercaria. DH IH Intermediate hosts of Heterophyes heterophyes 2nd: Fish 1st: Pirenella conica Encysted metacercaria in fish muscles (infective stage)  Infective stage: Encysted metacercaria Mode of infection: Man acquires the infection by ingestion of the encysted metacercaria (infective stage) in insufficiently cooked or inadequately salted fish (Feseekh) Diagnostic stage: Eggs in stool Heterophyes heterophyes Egg (diagnostic stage) Shape : Oval Shell: Thick Size: 30 x 15 µm Color: Yellow Content: mature Character: Operculated  Pathogenesis and clinical manifestations of heterophyiasis 1. Light infection: asymptomatic. 2. Heavy infection: inflammation of the intestinal mucosa where adult attach, resulting in chronic intermittent mucous diarrhea, abdominal pain. 3. Occasionally, egg emboli (due to the presence of genital sucker and the small size of the eggs) may pass through the mesenteric lymphatics and blood vessels to the heart, brain causing serious complications  Diagnosis of heterophyiasis 1. Clinical: abdominal pain and diarrhoea with a history of eating insufficiently cooked or salted fish especially after Eastern or in a patient coming from an endemic area. 2. Laboratory: finding the characteristic egg in repeated stool examination by direct smear or after stool concentration. Treatment: Praziquantel  Prevention and control 1. Proper diagnosis and treatment of patients. 2. Avoidance of eating insufficiently cooked or grilled fish. 3. Avoidance of feeding dogs and cats with raw fish especially in endemic areas. 4. Snail control by molluscicides.  A 33-year-old fisherman from Borolls area presented to the hospital complaining of abdominal pain and diarrhea of 2 weeks duration. On examination the patient had slight abdominal tenderness. As a fisherman, he used to eat semi-grilled fish while in fishing trips. Stool examination revealed small operculated 30 x 15 µm eggs. Metagonimus yokogawi “Metagonimiasis”  Distribution: Far East. Russia, Spain Habitat: Small intestine, embedded between villi. DH: Man, and fish-eating animals (dogs, cats, pigs). IH: It requires two IH 1st: Fresh water snail (Semisulcospira libertine), 2nd: Cyprinoid and Salmon fish. RH: Dogs and cats. Life cycle, infective stage, diagnostic stage, clinical manifestations, diagnosis and treatment as Heterophyes heterophyes. Morphology Pear-shaped, unsegmented, 1-1.2 mm, it has two suckers: oral ands ventral sucker, the latter is displaced to one side. No genital sucker. Simple intestinal caeca, one spherical ovary and 2 oval obliquely situated testes posterior part.  Fasciolopsis buski (Giant Intestinal Fluke) “Fasciolopsiasis”  Distribution: Far East. Habitat: Small intestine, attached to intestinal mucosa. DH: Man. IH: Fresh water snail (Segmentina) RH: Pigs. Morphology Largest intestinal trematode, 4-7 cm x1.5, ovale body ventral sucker is larger than oral sucker with simple wavy intestinal caeca. One branched ovary in the middle of the body and 2 branched testes in the posterior half with long cirrus sac. Life Cycle of Fasciolopsis buski Mode of infection DH IH  Infective stage: Encysted metacercaria. Mode of infection: Man acquires the infection by ingestion of the encysted metacercaria (infective stage) on raw or undercooked water plants. Diagnostic stage: Eggs in stool  Pathogenesis and clinical manifestations of fasciolopsiasis 1. Light infection: asymptomatic or mild abdominal pain and diarrhea due to inflammation and ulceration of intestinal mucosa 1. Heavy infection: severe inflammation and ulceration of mucosa with toxic metabolites absorption leading to diarrhea, nausea, vomiting, protein losing enteropathy. 3. Complication: hypoalbuminemia, fascial and generalized edema, ascites, vitamin B12 deficiency, anemia, malnutrition, allergic manifestations. Intestinal obstruction may occur.  Diagnosis of fasciolopsiasis 1. Clinical: abdominal pain and diarrhea with a history of eating raw aquatic plants patient coming from an endemic area. 1. Parasitological: finding the characteristic egg in repeated stool examination by direct smear or after stool concentration. 1. Complete blood count CBC: eosinophilia and megaloblastic anemia  Treatment: Praziquantel + ttt of hypoalbuminemia and anemia  Prevention and control 1. Proper diagnosis and treatment of patients. 2. Avoidance of eating insufficiently cooked water plants. 3. Avoidance of using human and pig feces for fertilization of water plants. 4. Snail control by molluscicides.