Ascariasis

Ascariasis is defined as a condition caused by round worm, the parasite Ascaris lumbricoides as a result of eating contaminated foods and  the human feces with Ascaris eggs. The disease infects over billions people around the globe, mostly in the third world.

I. Signs and symptoms
1. Intestinal obstruction 
In the study to describe the occurrence and management of bowel obstruction caused by Ascaris lumbricoides, a common parasite in warm climates that affects children with limited socioeconomic means, researchers at the Universidad Nacional de Colombia, Hospital de La Misericordia, showed that
physicians should have a high index of suspicion for parasitic infestation in warm climates where economically deprived children present with symptoms of intestinal obstruction. Ascaris lumbricoides may be the cause of these events in endemic areas(1).

2. Persistent cough, shortness of breath, wheezing
The affects of  hatching eggs of the round worm travel from the intestine  through the bloodstream or lymphatic system to the lungs where they are coughed up and swallowed can cause the symptoms of persistent cough, shortness of breath, wheezing, etc.

3. The adult round worm in the intestine where they grow and die can cause the symptoms of
a. abdominal pain, tenderness and bloating
Ascariasis is the most common helminthic infection in developing countries. It may cause chronic abdominal pain, tenderness and bloating(2). 

b. Nausea and vomiting
The symptoms are caused by toxin released by the round worm.

c. Bloody stools
It is a ewsult of inflammation caused by large numbers of Ascaris lumbricoides

4. Bowel obstruction
Bowel obstruction  can be caused by a large number of worms and various toxins released by the worms(3).

5. The presence of large numbers of round worm can cause symptoms
Severe abdominal pain, fatigue, vomiting, weight loss as the result of toxin released by large numbers of the adult worms and malnutrition.

6. In children
The presence of large numbers of roun woem can cause symptoms of the pain in periumbilical area, abdominal distension, interloop fluid, free fluid in the pelvis, etc(4).

7.  Malnutrition
There is a report of a case of a child three years old, with severe malnutrition as complication of Ascaris lumbricoides infection. Intestinal nematodes infect many of the world's children and constitute a formidable public health problem. The infected children may suffer nutritional deficits, serious illness and occasionally death(5).

8. Etc.

II. Causes and Risk factors
A. Causes
Ascariasis is a result of eating contaminated foods and  the human feces with Ascaris eggs.

B. Risk factors 
1. Children with male gender
Boys who live in the third world are the increased risk to develop Ascariasis. In the prospective study of 360 patients, researchers found that the male to female ratio was 1.37:1. 187 patients (52%) presented within 2-4 days of duration of illness. Mean +/- standard deviation (SD) age of patients was 6.35 +/- 2.25 years. Age group of 4-7 years (80%) was commonest group affected(6).


2. Trauma and tropical disease
There is a report of  a case of heavy intestinal infestation with Ascaris lumbricoides complicating the surgical management of a gunshot injury to the abdomen. Co-existent traumatic and infectious pathologies in this case highlight the complex burden of illness among children living in areas of violent conflict, with clinical relevance to trauma surgeons in the tropics(7).

3. Household cluster
Analysis of such data established that individuals are predisposed to infection with few or many worms and members of the same household tend to harbor similar numbers of worms. These effects, known respectively as individual predisposition and household clustering, are considered characteristic of the epidemiology of ascariasis. The mechanisms behind these phenomena, however, remain unclear, according to Dr. Walker M and the research team at the School of Public Health, Imperial College London(8). 

4. Poor sanitation
Use of human feces as fertilizer in the under developing world can increase the risk of  Ascariasis.

5. Etc.

III. Complications and diseases associated with Ascariasis
1. Pancreatitis
There is a report of  a 59-year-old female patient who was admitted for acute abdominal pain, having had several previous similar events before one of them was diagnosed as acute idiopathic pancreatitis. On admission, her physical exam was normal. Laboratory results showed hemoglobin 12.2 g/dL, white blood cell count 11 900 cells/mm(3), eosinophils 420 cells/mm(3), serum amylase 84 IU/mL, lipase 22 IU/mL and normal liver function tests. Abdominal ultrasound and a plain abdominal X-ray were also normal. An upper endoscopy showed round white worms in the duodenum and the stomach, some of them with bile in their intestines. The intestinal parasites were diagnosed as Ascaris lumbricoides(9)

 2. Esophageal space-occupying lesion
There is a report of an old female presented with dysphagia after an intake of several red bean buns and haw jellies. The barium meal examination revealed a spherical defect in the lower esophagus. Upper gastrointestinal endoscopy was done to further confirm the diagnosis and found a live Ascaris lumbricoides in the gastric antrum and two in the duodenal bulb(10).

3. Others
Ascaris infection is acquired by the ingestion of the embryonated eggs. The larvae, while passing through the pulmonary migration phase for maturation, cause ascaris pneumonia. Intestinal ascaris is usually detected as an incidental finding. Ascaris-induced intestinal obstruction is a frequent complication in children with heavy worm loads. It can be complicated by intussusception, perforation, and gangrene of the bowel. Acute appendicitis and appendicular perforation can occur as a result of worms entering the appendix. HPA is a frequent cause of biliary and pancreatic disease in endemic areas. It occurs in adult women and can cause biliary colic, acute cholecystitis, acute cholangitis, acute pancreatitis, and hepatic abscess. RPC causing hepatic duct calculi is possibly an aftermath of recurrent biliary invasion in such areas, according to the study by Dr. Khuroo MS. at the Sher-i-Kashmir Institute of Medical Sciences, Soura, Srinagar(11).

4. Etc.

IV. Diagnosis
After completing the physical examination and family history is recorded, the tests which your doctor order, include
1. Stool test
The aim of the test is to diagnose the presence of worm and egg in the stool.

2. Blood test 
The aim of the blood test is to diagnose for the presence of Eosinophil granulocyte, the white blood cells are  responsible for combating multicellular parasites and certain infections. There is a report of a  case of Ascaris-induced eosinophilic pneumonitis in an HIV-infected patient is described. Owing to his HIV status and the absence of peripheral blood eosinophilia on admission, the initial diagnosis was incorrect until the passage of two worms in his stool(12).

3. Abdominal X-rays
Abdominal X-rays is to test for the presence of the worm in the abdomen.

4. Ultrasound
the aim of the ultrasound is to check for the presence of worm in the internal organs.

5. CT scans or MRI
The CT scan and MRI is to allow the doctor to examine the internal organs and their surrounding area, such as blocking ducts in your liver or pancreas to test for the presence of worms.

6. Etc.

 V. Prevention
If you are traveling to the rural in the third world
1. Wash you hands with soap before handing foods
2. Avoid using public washroom if you can
3. Cook you foods and water before consuming
4. Other researchers suggested that With the 3-year's intervention, the Ascaris lumbricoides infection rates decreased from 17.81% to 2.52%, the rate of mass chemotherapy was 81.65%, which covered more than 6.2 million person-time, the awareness rates of parasitic disease control knowledge among the residents raised from 45.11% to 95.99%, and 84.09% of local people were supplied with safe water and 50.30% of families had sanitary toilets(13).
According to the World Health Organization,  preschool and school-age children, women of childbearing age (including pregnant women in the 2nd and 3rd trimesters and lactating women) and adults are at the high risk of heavy infections.

VI. Treatment
A. Medication
The primary medication used to treat Ascariasis, including the recommendation of WHO by killing the worm with side effects of diarrhea and abdominal pain
Researchers at the Instituto de Biomedicina. Facultad de Medicina, UCV., showed that in addition to the WHO recommended drugs (albendazole, mebendazole, levamisole, and pyrantel pamoate), new anthelmintic alternatives such as tribendimidine and Nitazoxanide have proved to be safe and effective against A. lumbricoides and other soil-transmitted helminthiases in human trials. Also, some new drugs for veterinary use, monepantel and cyclooctadepsipeptides (e.g., PF1022A), will probably expand future drug spectrum for human treatments(14).


B. Surgery
The aim of the surgery is to repair the damage caused by the worm and treatment of the medication, such as  Intestinal obstruction, bile duct obstruction, bleeding, thromboembolism, perforation, etc(15)(16).
Sources
(1) http://www.ncbi.nlm.nih.gov/pubmed/8632280
(2) http://www.ncbi.nlm.nih.gov/pubmed/20447214
(3) http://www.ncbi.nlm.nih.gov/pubmed/22262337 
(4) http://www.ncbi.nlm.nih.gov/pubmed/20143068
(5) http://www.ncbi.nlm.nih.gov/pubmed/9173412
(6) http://www.ncbi.nlm.nih.gov/pubmed/20143068
(7) http://www.ncbi.nlm.nih.gov/pubmed/20431222
(8) http://www.ncbi.nlm.nih.gov/pubmed/21541362
(9) http://www.ncbi.nlm.nih.gov/pubmed/20447214
(10) http://www.ncbi.nlm.nih.gov/pubmed/22509089
(11) http://www.ncbi.nlm.nih.gov/pubmed/8863040
(12) http://www.ncbi.nlm.nih.gov/pubmed/17264245
(13) http://www.ncbi.nlm.nih.gov/pubmed/22263492
(14) http://www.ncbi.nlm.nih.gov/pubmed/20701574
(15) http://www.ncbi.nlm.nih.gov/pubmed/20037884
(16) http://www.ncbi.nlm.nih.gov/pubmed/21698086