7321 - Amebiasis

Removed from the rating schedule effective May 19, 2024

DBQ: Link to Index of DBQ/Exams by Disability for DC 7321

Definition

Entamoeba (E) histolytica is the cause for amebiasis which is commonly asymptomatic, but may produce clinical signs and symptoms ranging from mild diarrhea to severe dysentery (see Diagnostic Code: 7322 Dysentery, bacillary). The E. histolytica is a protozoan parasite.

Etiology

The organism E. histolytica consists of two forms; the trophozite and the cyst. The trophozite form nourishes itself by feeding on bacteria and tissues, and then inhabits the lumen and the mucosa of the large intestine. It may invade other organs and tissues. Trophozites are found most often in liquid stools, but die once they are outside of the body. The cysts are found in formed stool and are unaffected by the environment. Cysts are passed from person to person or through food and water. High-risk groups include male homosexuals, and travelers and emigrants from areas in which the disease incidence is high.

Signs & Symptoms

Most persons display no symptoms, but consistently pass cysts in the stool. In addition, intermittent diarrhea, constipation, flatulence, and cramping pain occur. Tenderness over the liver and ascending colon may be presented, and blood and mucus may be found in the stool.

Amebic dysentery, which is common in the tropics but uncommon in temperate climates, manifests with frequent, semi-liquid stools that usually contain blood, mucus, and trophozoites. On examination, there may be abdominal tenderness, or severe abdominal pain and fever. Symptoms may diminish to some extent between relapses, but emaciation and anemia remain.

Tests

Intestinal amebiasis is confirmed by finding E. histolytica in the stool or tissues, and may require 3 to 6 specimens. At times, proctoscopy is done on patients who exhibit symptoms. The procedure often shows mucosal lesions which can be checked for trophozites. Other diagnostic measures include serologic tests, ultrasonography, and computed tomography (CT) scan. Serologic tests are positive in most persons with liver abscesses and in more than 80% of persons with amebic dysentery.

Treatment

Generally, the aim at treatment is to relieve symptoms, replace blood loss, and correct fluid and electrolyte imbalances.

Residuals

Amebas can travel through the portal circulation causing liver abscesses which can in turn travel via the liver or bloodstream to the lungs, brain or other organs causing infection. In addition, symptoms of subacute appendicitis may occur, and, in these instances, surgery may result in peritonitis.

Special Considerations

  • This disease shall be granted service connection as a result of tropical service, although not otherwise established as incurred in service if manifested to a compensable degree within the applicable time limits under 38 CFR 3.307 or 38 CFR 3.308 following service in a period of war or following peacetime service provided the rebuttable presumption provisions of 38 CFR 3.307 are also satisfied. [38 CFR 3.309 [Disease subject to presumptive service connection]

Notes

  • Amebiasis with or without liver abscess is parallel in symptomatology with ulcerative colitis and should be rated on the scale provided for the latter. Similarly, lung abscess due to amebiasis will be rated under the respiratory system schedule, diagnostic code 6809.

  • Ratings under diagnostic codes 7301 to 7329, inclusive, 7331, 7342, and 7345 to 7348 inclusive will not be combined with each other. A single evaluation will be assigned under the diagnostic code which reflects the predominant disability picture, with elevation to the next higher evaluation where the severity of the overall disability warrants such elevation.[38 CR 4.114]

  • There are diseases of the digestive system, particularly within the abdomen, which, while differing in the site of pathology, produce a common disability picture characterized in the main by varying degrees of abdominal distress or pain, anemia and disturbances in nutrition. Consequently, certain coexisting diseases in this area, as indicated in the instruction under the title “Diseases of the Digestive System,” do not lend themselves to distinct and separate disability evaluations without violating the fundamental principle relating to pyramiding as outlined in 38 CFR 4.14[38 CFR 4.113]