AmoebiasisClinical Case 10

Ellen Marie de los Reyes

EF, a fresh college graduate, is applying for a job at a pharmaceutical company. Routine laboratory examinations were requested. Fecalysis revealed (+) E histolytica cyst. Patient is asymptomatic.

1. Give your Diagnosis

Amoebiasis

An infection with Entamoeba histolytica produced by the ingestion of cysts in the organism

In the intestines, the cysts develop into trophozoites that adhere to colonic epithelial cells by means of a lectin on the parasite

Amoebiasis Lyses the host cell invades the submucosa and

secretes IFN-γ activated macrophages

This will result in dysentery The parasite can invade the liver

and can develop liver abscesses and an amoebic granulomas developing in the intestinal wall

Symptoms gastrointestinal including diarrhoea, vomiting,

abdominal pain or discomfort and fever. Duration: few days to a few weeks but usually it

is about two to four weeks. Most are asymptomatic has the potential to make the sufferer

dangerously ill Infections that sometimes last for years may be

accompanied by no symptoms (in the majority of cases), vague gastrointestinal distress, dysentery (with blood and mucus).

Asymptomatic Infection the amoeba lives by eating and digesting

bacteria and food particles in the gut. It does not usually come in contact with the

intestine itself due to the protective layer of mucus that lines the gut.

Disease occurs when amoeba comes in contact with the cells lining the intestine.

secretes toxic substances, including enzymes that destroy cell membranes and allow it to penetrate and digest human tissues, resulting in flask-shaped ulcers in the intestine.

Amoebiasis Amoebiasis is transmitted:

fecal contamination of drinking water foods

direct contact with dirty hands sexual contact

2. How would you manage this case?

Main drugs

Metronidazole Tinidazole Diloxanide

*These agents may be used in combination

Drugs of choice for various forms of Amoeboisis

Acute invasive intestinal amoeboisis resulting in acute severe amoebic dysentary> metronidazole followed by diloxanide

Chronic intestinal amoeboisis>diloxanide

Heptic amoeboisis>metronidazole followed by dilxanide

Carrier state>diloxanide

3. Discuss the pharmacokinetics of the drug of choice.

Metronidazole

Kills the trophozoites of E. histolytica by damaging the DNA by toxic oxygen products generated by thedrug

But has no effect on the cysts Most effective drug available for

invasive amoebiasis

Pharmacokinetics Usually given orally Rapidly, completely absorbed Peak plasma concentration 1-3 hrs Half-life 7 hrs Distributed rapidly through the tissues

reaching high concentrations in the body fluids and CSF

Some are metabolized and most excreted in urine

Unwanted effects

Bitter taste in the mouth Minor gastrointestinal disturbances Dizziness, headache, sensory

neuropathies Drug interferes with alcohol

metabolism

Tinidazole

Similar to metronidazole Eliminated more slowly Half-life 12-14 hrs

Diloxanide

Effective against the non-invasive intestinal parasite

Drugs have a direct amoebicidal action affecting the amoebae before encystment

Given orally No serious adverse effects

And now we reached the end!Thank you!