METHODICAL INSTRUCTIONS FOR THE VI COURSE STUDENTS
MEDICAL FACULTY
LESSONS № 2 (PRACTICAL – 6 HOURS)
Theme 1. Differential diagnosis of chronic diarrheal syndrome in the clinic of infectious diseases (amebiasis, balantydiasis, giardiasis, intestinal helminthiasis – ascariasis, tryhocephalosis, enterobiosis) with chronic diseases of dygestive system. Problem of helminthoses diagnosis in Ukraine. Features of clinical course, diagnosis and differential diagnosis of helminthoses (trichinosis, stronhiloyidosis, toksokarosis, opisthorchosis, himenolepidosis, teniarinhosis, teniosis) – 6 hours.
Aim: to study clinical and laboratory manifestation, diagnostics, treatment and prophylaxis of amebiasis, balantydiasis, giardiasis, intestinal helminthiasis – ascariasis, tryhocephalosis, enterobiosis trichinosis, stronhiloyidosis, toksokarosis, opisthorchosis, himenolepidosis, teniarinhosis, teniosis.
Professional orientation of students:
Acute intestinal infectious disease caused by Entamoeba histolytica. It is most commonly asymptomatic but symptoms ranging from mild diarrhea to dysentery may occur.
There are 2 forms of E. histolytica: motile trophozoite and a cyst. The trophozoite, parasitic form, dwells in the bowel lumen, where it feeds on bacteria or tissue. With diarrhea, the fragile trophozoites pass unchanged in the liquid stool and rapidly die. If diarrhea is not present, the organisms usually encyst before leaving the gut.
Performed with irritable bowel syndrome, regional enteritis, and diver ticulitis. Amebic dysentery may be confused with salmonellosis, schistosomiasis or ulcerative colitis.
Hepatic amebiasis and amebic abscess must be differentiated from other hepatic infections, including abscesses due to bacterial infection and infected echinococcus cysts.
Balantidium coli exists in either of two developmental stages: Trophozoites and Cysts. In the trophozoite form, they can be oblong or spherical, and are typically 30 to 150 µm in length and 25 to 120 µm in width. It is its size at this stage that allows Balantidium coli to be characterized as the largest protozoan parasite of humans. Trophozoites possess both a macronucleus and a micronucleus, and both are usually visible. The macronucleus is large and sausage-shaped while the micronucleus is less prominent. At this stage, the organism is not infective but it can replicate by transverse binary fission.
In its cyst stage, the parasite takes on a smaller, more spherical shape, with a diameter of around 40 to 60 µm. Unlike the trophozoite, whose surface is covered only with cilia, the cyst form has a tough wall made of one or more layers. The cyst form also differs from the trophozoite form because it is non-motile and does not undergo reproduction. Instead, the cyst is the form that the parasite takes when it causes infection.
he first study to generate Balantidiasis in humans was undertaken by Cassagrandi and Barnagallo in 1896. However, this experiment was not successful in creating an infection and it was unclear whether Balantidium coli was the actual parasite usedThe first case of Balantidiasis in the Philippines, where it is the most common, was reported in 1904. Currently, Balantidium coli is distributed worldwide but less than 1% of the human population is infected. Pigs are a major reservoir of the parasite, and infection of humans occurs more frequently in areas where pigs comingle with people. This includes places like the Philippines, as previously mentioned, but also includes countries such as Bolivia and Papua New Guinea. But pigs are not the only animal where the parasite is found. In a Japanese study that analyzed the fecal samples in 56 mammalian species, Balantidium coli was found to be present not just in all the wild boars tested (with wild boars and pigs being considered the same species), it was also found in five species of non human primate: Chimpanzee (Pan troglodytes), White-handed gibbon (Hylobates lar), Squirrelmonkey (Saimiri sciurea), Sacred baboon (Comopithecus hamadryas), and Japanese macaque (Macaca fuscata). In other studies, Balantidium coli was also found in species from the orders Rodentia and Carnivora.
Since Balantidiasis is not a very common disease, patient history is important in diagnosis. If the patient has recently been exposed to amebiasis (intestinal illness caused by Entamoeba histolytica) through travel or contact with infected individuals combined with diarrheal symptoms, then consider diagnosis of balantidiasis. Also, ask if patient has been in contact with pigs as contact increases the risk of infection.
Balantidiasis can be diagnosed through sampling of the patient’s stools and searching for cysts or trophozoites under a microscope. One can also perform a colonoscopy or sigmoidoscopy to visually examine the intestinal lining and to obtain a biopsy from the large intestines can also provide evidence for the presence of trophozoites.
Today, Giardia continues to affect large populations of people world wide. In developed nations, Giardia infects 2–5% of the population acutely, people who carry cysts may not know they are infected, as currently there is no treatment for Giardia cysts in the large intestine. In developing countries with poor sanitation and contaminated food or water sources, Giardia may affect up to 20–30 % of the population acutely. It is also the most commonly diagnosed enteric parasite in the United States and Canada.
Pregnant patients who are infected but asymptomatic are advised not to receive treatment for Giardia because there are underlying risks in current therapies. For instance, metronidazole is rapidly absorbed and easily enters fetal circulation. Studies have shown mixed results regarding the adverse effects of metronidazole on the development of the fetus. One retrospective study involving 1469 women who took Metronidazole during the first trimester of pregnancy showed no adverse effects on the fetus. However, in the Collaborative Perinatal Project with over 50,000 mother-child pairs, the infants of 31 mothers who took metronidazole during the first trimester of pregnancy were found to developed drug-associated malformation. These older studies are nowadays under attack and considered flawed. More recent studies conclude that “the current data do not support a significant increased risk for birth defects or other adverse effects on the fetus.” Paromomycin is the choice of drug for treating pregnant women infected with Giardia because it is poorly absorbed by the mother and excreted almost 100% in feces; hardly any of the drugs would reach the fetus.
Roughly 1.5 billion individuals are infected with this worm, primarily in Africa and Asia. Ascariasis is endemic in the United States including Gulf Coast; in Nigeria and in Southeast Asia. One study indicated that the prevalence of ascariasis in the United States at about 4 million (2 %). In a survey of a rural Nova Scotia community, 28.1 % of 431 individuals tested were positive for Ascaris, all of them being under age 20, while all 276 tested in metropolitan Halifax were negative. Deposition of ova (eggs) in sewage hints at the degree of ascariasis incidence. A 1978 study showed about 75 % of all sewage sludge samples sampled in United States urban catchments contained Ascaris ova, with rates as high as 5 to 100 eggs per litre]. In Frankfort, Indiana, 87.5 % of the sludge samples were positive with Ascaris, Toxocara, Trichuris, and hookworm]. In Macon, Georgia, one of the 13 soil samples tested positive for Ascaris]. Municipal wastewater in Riyadh, Saudi Arabia detected over 100 eggs per litre of wastewater and in Czechoslovakia was as high as 240–1050 eggs per litre.
Ascariasis can often be measured by examining food for ova. In one field study in Marrakech, Morocco, where raw sewage is used to fertilize crop fields, Ascaris eggs were detected at the rate of 0.18 eggs/kg in potatoes, 0.27 eggs/kg in turnip, 4.63 eggs/kg in mint, 0.7 eggs/kg in carrots, and 1.64 eggs/kg in radish. A similar study in the same area showed that 73% of children working on these farms were infected with helminths, particularly Ascaris, probably as a result of exposure to the raw sewage.
Methodology of Practical Classes: 9.00-11.15 hours in 6-hours class
1. Basic symptoms of amebiasis and balantydiasis.
2 Source of infection of amebiasis and balantydiasis.
3. Ways and main aspects of amebiasis and balantydiasis
4. Methods of specific diagnostics.
5. Source of infection at intestinal helminthiasis.
6. Ways and main aspects of intestinal helminthiasis.
7. Pathogenesis of intestinal helminthiasis.
8. Basic symptoms of intestinal helminthiasis.
9. Clinical classification.
10. Complications of intestinal helminthiasis.
11. Examination plan for patient with supposed intestinal helminthiasis.
14. .Methods of specific diagnostics.
15. Differential diagnosis.
16. Indications for etiotropic therapy. Drugs, dosing, ways of administration and duration of treatment.
17. Prophylaxis of intestinal helminthiasis.
Algorithm of students’ communication with patient with pathology in subject (communication skills ) (for clinical department).
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Discipline |
To know |
To be able to |
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Microbiology |
Microbiological, virological, serological, biological, microscopic and immunologic methods of examination used in diagnostics of infectious diseases |
Take samples of material for examination, estimate results of testing |
|
General and pathological anatomy, histology. |
Topography, structure and histology of different organs and systems being affected by infectious diseases |
Define the location and main anatomic features of affected organs |
|
Normal and pathological physiology |
Functions of organs and systems, types of failures caused by infectious process. Aspects of physiological standard of human organs and systems; aspects of positive laboratory examination |
Estimate results of laboratory examination |
|
Propedeutics of medical diseases |
Main stages and methods of patient clinical examination |
Make up medical history, perform clinical examination of the patient by different organs and systems, define clinical symptoms of pathology. Analyze obtained results |
|
Immunology and allergology |
Key terms of the discipline, role of immunity system in infectious process, influence on the term of germ elimination from human organism. Immunological aspects of complications |
Analyze data of immunological examinations |
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Dermatology |
Characteristics of different types of exanthema and enanthema |
Define the nature of rash |
|
Surgery |
Clinical and laboratory aspects of acute surgical disorders in intestinal helminthiasis |
Diagnose acute surgical pathology and define the ways of patient’s behavior |
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Clinical pharmacology |
Pharmakokinetics and pharmakodynamics, adverse effects of etiotropic drugs, ways of pathogenic therapy |
Prescribe treatment with regard to age, individual symptoms of the patient, chose an optimum mode of drug intake and dosage, provide prescriptions |
Other disciplines |
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Family practice |
Pathogenesis, epidemiology, intensiveness of clinical signs, possible complications of infectious diseases. Principles of prophylactics and treatment |
Perform differential diagnostics of infectious and non-infectious diseases |
Integration between subjects |
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Virulent diseases |
Features of infectious diseases. Methods of diagnostics, treatment and prophylactics of infectious diseases. |
Perform differential diagnostics of infectious diseases. |
Seminar discussion of theoretical issues: – 11.45-13.15 hours in 6-hours class
Tests evaluation and situational tasks.
1. 1 Drug of choice for sanation of the carriers of amoeba cysts can be.
A. Monomicyn
B. Delagil
C. Tetracycline
D. Yatren
E.Ursosan
2. What agent causes balantidiasis.
A. B. Coli
B. B. Enterocolitica
C. S. Derby
D. S. Boydi
E.L. Canicola
3. In what disease mucous, erythrocytes, eosinophils, plasma cells and crystals Charcot-Leiden were in stool analysis reveals.
A. Intestinal amoebiasis
B. Intestinal yersiniosis
C. Shigellosis
D. Balantidiasis
E.Enterohaemorrhagic esherichiosis
4. The complications of balantidiasis can be all except:
A. Hypochromic anemia
B. Intestinal bleeding
C. Perforation ulcers
D. Liver abscess
E.Cachexia
5. What is the epidemiology of enterobiosis?
A. Zoonosis
B. Wound helminthiasis
C. Percutaneous helminthiasis
D. Contagious helminthiasis
E.Transmissive helminthiasis
6. What is the place of the parazitising of the agent in strongyloidosis?
A. Upper sections of a small intestine
B. Large intestine (sigmoid)
C. Large intestine (caecum)
D. Bile ducts
E.Liver
7. What are the main clinical sighs of the early stage of ancylostostomiasis?
A. Dermatitis (polymorphic rash, itch)
B. Damage of the respiratory tract (bronchitis, laryngotracheitis, eosinophilic infiltrates)
C. Fever
D. Eosinophilia (30-60 %)
E.All are corect
8. What is the epidemiology of cystecercosis?
A. The infection is an endogenic (autoinvasion)
B. The human is the definitive host
C. The pigs are an intermediate host
D. The human is an intermediate host
E.All are correct
9. B-12 deficiency is cause by which of the following:
A. Echinococus granulosis
B. T. saginata
C. E. multilocularis
D. Diphyllobothrium latum
E.Ascaris lumbricoideus
10. Trichinosis belongs to:
A. Nematodosis
B. Trematodosis
C. Cestodosis
D. Ricketsiosis
E.Mycosis
11. What is the duration of the life of the adult forms in echinoccosis?
A. It is continued from 6 months till 1 year
B. It is continued till 1 month
C. It is continued from 1 year till 3 years
D. It is continued more than 3 years
E.It is continued 7 days
12. What is epidemiology of hymenolepidosis?
A. It is percutaneous helminthiasis
B. It is not contagious helminthiasis
C. It is peroral helminthiasis
D. It is transmissive helminthiasis
E.It is especially dangerous disease
13. How to increase frequency of findings of cyst of lamblias in fresh incandescence and vegetative forms in duodenal content?
A. Cultivation in thermostat
B. By the method of floatation in bilious clear soup
C. Cultivation in anaerobic chamber
D. By the applications of phase-contrast and lumencense microscopy with the help of methylen-orange
E.To sow on a nourishing environment
14. The most effective means of filariasis control will be:
A. Yatren therapy
B. Insecticidal measures against culex mosquitoes
C. Provision of underground drainage
D. Personal prophylaxix
E.All mentioned above
15. Causative agent of Giardiasis is:
A. G. lamblia
B. G. intestinalis
C. G. lamblia and G. intestinalis
D. B. coli
E.None of the above
16. What is the main symptom of the Trichinellosis:
A. Rash
B. Muscle pain
C. Edema of eyelids
D. Nodules in muscles
E.All mentioned above
17. Which of the following is the largest intestinal helminthes in human:
A. D. latum
B. S. stercoralis
C. Anisakis simplex
D. E. vermicularis
E.T. saginatus
18. Loffler’s syndrome in ascariasis is due to:
A. Inflitration of payer’s patches by eosinophills
B. Invasion of gallblader by A.lumbricoides pathogen
C. Inflitration of lung tissue by eosinophills
D. Inflitration of liver by eosinophills
E.None of the above
Real life situation to be solved:
1. Patient P., 36 years old, a farmer is seriously ill, with high temperature, having chills, headache, flatulence, nauseA. At present he is complaining of severe abdominal pain, diarrhea up to 15 times a day stool is liquid, smelly, with impurities mucous and blood. His eyes are sunken. The tongue is covered with white coating. On palpation- painful colon, increased liver. In blood – neutropil leukocytosis with a shift formula the left anemiA. On rectomanoscopy deep ulcers with irregular edges are observed, including along the folds. What is the diagnosis.
a. Shigellosis
b. Balantidiasis
c. Nonspecific ulcerous colitis
d. Amoebiasis
e. Colon tumor
2. A 29 years old patient T. works on a pig farm. She was hospitalized with symptoms of balantidiasis. What would be the drug of choice.
a. Benzylpenicillin
b. Gentamycin
c. Chloramphenicol
d. Monomycin
e. Timogen
3. Patients with аmebiasis has been hospitalized. For specific therapy are used so-called, indirect and аmebiostic tissue, and preparations with universal action. What group does delagin belong to?
a. Tissue аmoebiostic
b. Indirect аmoebiostic
c. Lines of аmoebiostic
d. Preparations with universal action
e. Does not belong to anyone
4. A patient was admitted in hospital with complaints of abdominal pain, increased body temperature, diarrheA. Stool is liquid, smelly, with mixture of mucus and blood. What kind of illness need to think about in the first place?
a. Balantidiasis
b. Rotavirus gastroenteritis
c. Food poisoning
d. Amoebiasis
e. Giardiasis
5. Woman 24, complaints of heaviness in the area of liver during 3 days, with an irradiation in the back. Signs of icterus are not present. Last menstruation – 5 weeks ago. Appointed ultrasonic research of abdominal region and small pelvis was, found marked progress uterogestation. Expansion of common biliary tract, inflammation of gall-bladder, bulge of its its wall, presence of crystal sediment, extended loops of small intestines are visualized. Investigation of colonoscopy found additional exogenic structures as a “ribbon”, which is displaced in intestine and changes form without distal acoustic shade. Most probable diagnosis is:
a. Ascaridosis
b. Partial intestinal uncommunicating
c. Acute calculary cholecystitis
d. Choledocholithiasis
e. Cholecystitis
6. Patient, 27 years old, complaints of itching in perianal area, which is present in evening before sleep. It continues for 1-3 days and disappears independently, but reconvolense afterwards. Most probable diagnose will be:
a. Trichinosis
b. Enterobiosis
c. Ascaridosis
d. Helminthosis
e. Cystitis
1. etiology of amebiasis, balantydiasis, intestinal helminthiasis.
2. stages of pathogenesis.
3. clinical signs of amebiasis, balantydiasis, intestinal helminthiasis.
4. pathogenesis, genesis term and clinical aspects of amebiasis, balantydiasis, intestinal helminthiasis.
5. amebiasis, balantydiasis, intestinal helminthiasis laboratory diagnostics
6. the ways of treatment
7. principles of prophylactis
8. medical approach in case of emergencies
9. rules of discharging of patients from in-patient hospital
The student should be able to:
– make up epidemiological anamnesis of the disease and define possible routes and aspects of infection transmission;
– solve the issue of necessary hospitalization of the patient to infectious clinic;
– prepare and submit proper documentation to sanitary and epidemiological station.
– keep basic rules at the bedside;
– prepare medical history with epidemiologic evidence estimation;
– examine a patient and detect basic amebiasis, balantydiasis, intestinal helminthiasis symptoms and syndromes, prove clinical diagnosis for timely referral to treatment;
– make differential diagnostics;
– identify possible complications and emergencies on basis of clinical examination;
– make patient’s examination plan;
– interpret laboratory examination results;
– make individual treatment plan
– make recommendations concerning regimen, diet, examination, observation during convalescent period.
Correct answers of tests evaluation and situation tasks:
1. D
2. A
3. A
4. D
5. D
6. A
7. E
8. E
9. D
10. A
11. A
12. C
13. D
14. D
15. C
16. E
17. D
18. C
Real life situation:
1. B
2. D
3. A
4. A
5. A
6. B
2.Bibhat K. Mandal, Edmund G.L. Wilkins, Edward M. Dunbar, Richard T. Mayon-White Infectious diseases. – Panther Publishers Private Limited, 1999. – P. 314-327.
3. D.R. Arore, B. Arore Medical Parasitology. – CBS Publishers & Distributors, 2002. – 233 p.
4. Berkow R. The Merck Manual of diagnosis and therapy. – Merck Sharp, 1987. – P. 81-82; 98-101, 183-186.
The methodical instruction has been worked out by the instructor: by Vasyl Kachor
Methodical instruction was discussed and adopted at the Department sitting
14.06.13 Minute N 10
Methodical instruction was discussed and reviewed at the Department sitting
__________201_ Minute N ___
