NematodesNematodes By Dr. Osman Bukhari By Dr. Osman Bukhari

NematodesNematodes:: 1- 1- Human Intestinal nematodes Human Intestinal nematodes 2-Tissue dewelling nematodes 2-Tissue dewelling nematodes 3- 3- Animal nematodesAnimal nematodes

1- 1- Human Intestinal nematodesHuman Intestinal nematodes - T. trichuria - E. - T. trichuria - E. vermicularis - A. lumbricoides vermicularis - A. lumbricoides - Hook worms - S. stercolaris, - Hook worms - S. stercolaris, - C. phillipinensis- C. phillipinensis..

2-Tissue dewelling nematodes2-Tissue dewelling nematodes - Filarial - D. medinensis - Filarial - D. medinensis

3- 3- Animal nematodesAnimal nematodes - T. canis - A. braziliensis - T. canis - A. braziliensis - T. spiralis - T. spiralis

Human Intestinal nematodesHuman Intestinal nematodes - - Largest group of human helmithic infectionLargest group of human helmithic infection..

- Infection indicative of za - Infection indicative of za level of hygienelevel of hygiene and and sanitationsanitation in z community. in z community. Soil Soil pollutionpollution by human faeces is by human faeces is a major factor a major factor in transmissionin transmission. (SOIL transmitted worms.). (SOIL transmitted worms.)

- - Multiple infectionMultiple infection can occur. can occur.

- Clinical manifestations depend on - Clinical manifestations depend on worm worm loadload..

-Transmission is either: -Transmission is either: 1- direct 1- direct fecal-oralfecal-oral 2- modified 2- modified fecal-oral fecal-oral 3 3-- through skin penetration. through skin penetration.

Direct faecal oralDirect faecal oral: (: (E. vermicularis & T. E. vermicularis & T. trichuria)trichuria)

Infective eggs Adult in the bowelInfective eggs Adult in the bowel Modified direct faecal oralModified direct faecal oral: (: (A. lumbricoides)A. lumbricoides) Infective eggs small bowel & larvae Infective eggs small bowel & larvae

penetratepenetrate venules lungs small bowel adultvenules lungs small bowel adult Percutaneous or skin penetrationPercutaneous or skin penetration: :

((Hook worms)Hook worms) Eggs Rabditiform larvae Flariform larvaeEggs Rabditiform larvae Flariform larvae Skin Lungs Small bowel AdultSkin Lungs Small bowel Adult ((Strongyloides)Strongyloides) Rabditiform larvae Flariform larvae SkinRabditiform larvae Flariform larvae Skin Lungs Small bowel AdultLungs Small bowel Adult

TrichuriasisTrichuriasis - Infection is - Infection is world wideworld wide occurring under occurring under

unhygienic conditions.unhygienic conditions. - Adult lives in za - Adult lives in za caecum & adjacent bowelcaecum & adjacent bowel. .

InIn heavy infection in the heavy infection in the whole colonwhole colon - Human is za - Human is za principle hostprinciple host, specially , specially

children..children.. - - Infective stageInfective stage is za eggs & is za eggs & transmissiontransmission is is

direct fecal- oral.direct fecal- oral. - - Asymptomatic infection is commonAsymptomatic infection is common.. - Heavy infections: - Heavy infections: Bloody diarrhea Bloody diarrhea (colitis)(colitis) associated wz abd pain, tenesmus, associated wz abd pain, tenesmus,

anorexiaanorexia and Wt loss.and Wt loss.

- - Rectal prolapseRectal prolapse - - growth retardationgrowth retardation in children. in children. Associated Associated malnutritionmalnutrition & & other other parasitic infectionsparasitic infections play a role.. play a role..

- May cause - May cause appendicitisappendicitis

- - No signif. eosinophiliaNo signif. eosinophilia..

- Diag. : characteristic - Diag. : characteristic egg in za stoolsegg in za stools..

- Management: - Management: MebendazoleMebendazole 100mg 100mg x2x3 days, x2x3 days, Pyrentel pamoatePyrentel pamoate 10 mg/kg 10 mg/kg 3 tabs of 250 mg for adults., 3 tabs of 250 mg for adults., LevamesolLevamesol 3 tabs of 40mg for adults. 3 tabs of 40mg for adults.

EntrobiasisEntrobiasis - Institutional & - Institutional & familial diseasefamilial disease

specially in specially in childrenchildren.. - Associated with - Associated with poor hygienepoor hygiene.. - Eggs are za - Eggs are za infective stage infective stage

- transmission is - transmission is direct fecal direct fecal oraloral..

- Adult lives in za - Adult lives in za caecum & adjacent caecum & adjacent bowelbowel and have short life span and and have short life span and infection is infection is maintained by maintained by autoinfectionautoinfection..

- Most infections are - Most infections are asymptomaticasymptomatic.. - - Peri anal pruritusPeri anal pruritus & & abnormal abnormal

behaviorbehavior - - Pruritus vulvaePruritus vulvae in females. in females.

- - Mild GIT symptomsMild GIT symptoms.. - Migrating worms cause - Migrating worms cause ectopic ectopic

diseasedisease e.g. appendicitis, salpingitis. e.g. appendicitis, salpingitis. - - No significant eosinophiliaNo significant eosinophilia.. - - DiagnosisDiagnosis is by naked appearance is by naked appearance

of za adult and definitely by of za adult and definitely by finding finding eggseggs with adhesive cellophane tape with adhesive cellophane tape

- Diagnosis in a member necessitates - Diagnosis in a member necessitates ex of others..ex of others..

- All family members with symptoms - All family members with symptoms should be treated.should be treated.

- - MebendazoleMebendazole 100 mg , 100 mg , Pyrentel Pyrentel pamoatepamoate 3 tabs, 3 tabs, LevamesolLevamesol 3 tabs, 3 tabs, Piperazine 4gPiperazine 4g; All single dose & ; All single dose & repeated after 2 weeks.repeated after 2 weeks.

AscariasisAscariasis - - Most common human helmnithic Most common human helmnithic

infectninfectn

- Infection is common in all age - Infection is common in all age groups,groups,

specially childrenspecially children..

- - Eggs are za infective stage.Eggs are za infective stage. - -TransmissionTransmission is modified direct & is is modified direct & is enhanced by enhanced by high egg output.high egg output.

- Part of life cycle in za - Part of life cycle in za lungs.lungs.

- Most infections are - Most infections are asymptomatic asymptomatic and manifestatios depend on za and manifestatios depend on za intensity of infestation. intensity of infestation.

Clinical featuresClinical features::

- - asymptomaticasymptomatic..

- - LofflersLofflers ( respiratory symptoms) ( respiratory symptoms)

- - DyspepsiaDyspepsia, abdominal pain and , abdominal pain and patient may patient may vomit za worm or pass it vomit za worm or pass it in z stool.in z stool.

- - Obstructive manifestationsObstructive manifestations: small : small intestine, biliary and pancreatic duct intestine, biliary and pancreatic duct obstruction. Suppurative cholangitis obstruction. Suppurative cholangitis and appendicitis.and appendicitis.

- In malnourished children heavy - In malnourished children heavy infection have significant effects on infection have significant effects on nutrition and nutrition and developmentdevelopment - - Serious morbidity & mortality is rare Serious morbidity & mortality is rare - - DiagnosisDiagnosis by finding by finding characteristic eggs in characteristic eggs in the stools.the stools.

- - MebendazoleMebendazole 100 mg x2x3 , 100 mg x2x3 , Pyrentel Pyrentel pamoatepamoate 10 mg /kg 3tab, 10 mg /kg 3tab, LevamizolLevamizol 3 3 tab. tab. PiperazinePiperazine 4 g ( 75 mg / kg) 4 g ( 75 mg / kg) specially in obstructive disease.specially in obstructive disease.

- - Surgery in obstructionSurgery in obstruction if no resopnse if no resopnse to conservative management.to conservative management.

AnklystomiasisAnklystomiasis - Caused by - Caused by A. duodenale & N. A. duodenale & N.

americanusamericanus.. - Adults live in - Adults live in upper small bowelupper small bowel

attached to za mucosa by buccal attached to za mucosa by buccal capsules leading to capsules leading to blood lossblood loss..

- - Flariform larvaeFlariform larvae are za are za infective stageinfective stage and transmission is and transmission is through za skinthrough za skin..

- - Superficial position of za larvae in z Superficial position of za larvae in z soilsoil, , lacklack of safety disposal of human of safety disposal of human excreta and the habbit of walking bare excreta and the habbit of walking bare feet facilitate transmission & feet facilitate transmission & prevalence.prevalence.

Clinical featuresClinical features: : - Ground itch. - Ground itch.

- Lofflers syndrome.- Lofflers syndrome.

- Epigastric pain, dyspepsia & weight - Epigastric pain, dyspepsia & weight loss..loss..

- Iron deficiency & hypoprotienaemia.- Iron deficiency & hypoprotienaemia.

- Physical and mental retardation.- Physical and mental retardation.

- Positive occult blood in the stools.- Positive occult blood in the stools.

Diagnosis:Diagnosis: by finding eggs in za by finding eggs in za stools.stools.

- Treatment- Treatment::

- - MebendazoleMebendazole 100 mg X2X3 (95% cure 100 mg X2X3 (95% cure rate)rate)

and 99% reduction in egg load.and 99% reduction in egg load.

- - Pyrental pamoatePyrental pamoate 10 mg/kg (max 1gm) 10 mg/kg (max 1gm)

- - LevamizoleLevamizole 3 tabs 3 tabs

-- Piperazine Piperazine 75 mg/kg (4 gm) 75 mg/kg (4 gm)

- - Iron therapyIron therapy for anaemia for anaemia

- - High protein dietHigh protein diet

SrongyloidosisSrongyloidosis - High prevalence in za - High prevalence in za tropics.tropics.

- Adult lives in the small bowel - Adult lives in the small bowel - - Free living formsFree living forms occur in za soil. occur in za soil.

- - Potentially lethal in za Potentially lethal in za immunosupressedimmunosupressed because of because of overwhelming overwhelming hyper infectionhyper infection

- Larvae passed in z stools , become - Larvae passed in z stools , become infective in the soil & infective in the soil & penetrate za skinpenetrate za skin..

- - AutoinfectionAutoinfection can occur through lower can occur through lower GIT and peri anal region. GIT and peri anal region.

-- Clinical featuresClinical features include skin include skin itching, Lofflers, abdominal pain, itching, Lofflers, abdominal pain, diarrhea , malabsorption & protein diarrhea , malabsorption & protein losing enteropathy. Rarely perforation.losing enteropathy. Rarely perforation.

- - Eosinophilia ++++.Eosinophilia ++++. - Larva currens- Larva currens.. - 1/3 are - 1/3 are asymptomaticasymptomatic.. - - Massive larval invasionMassive larval invasion of z lungs, of z lungs,

brain, liver, heart & kidneys occur in brain, liver, heart & kidneys occur in autoinfection in z immunosupressed autoinfection in z immunosupressed (Hyper infection) and may be fatal. (Hyper infection) and may be fatal.

- - Hyper infectionHyper infection causes severe abd causes severe abd pain, diarrhea, ileus, pneumonia with pain, diarrhea, ileus, pneumonia with pulmonary infiltrations, pulmonary infiltrations, meningoencephalitis, sepsis and meningoencephalitis, sepsis and shock from gram negative shock from gram negative septicemia leading to death if not septicemia leading to death if not diagnosed & treated early.diagnosed & treated early.

DiagnosisDiagnosis by demonstration of by demonstration of larvae in za stools or jejunal aspirate larvae in za stools or jejunal aspirate or by serology.or by serology.

TreatmentTreatment: Aim of management is to : Aim of management is to eradicate the infection.eradicate the infection.

--ThiabendazoleThiabendazole 25 mg x2x3 25 mg x2x3 - - AlbendazoleAlbendazole 15 mg x2x3=may 15 mg x2x3=may need 2need 2ndnd course. course. - - IvermectinIvermectin 200 microg. 200 microg. Single dose or 2 daily doses.Single dose or 2 daily doses.

- Hyper infection needs prolonged - Hyper infection needs prolonged course and mortality is high.course and mortality is high.

- In endemic areas exclude the - In endemic areas exclude the infection before immunosuppressioninfection before immunosuppression..

Prevention of NematodesPrevention of Nematodes

- Improvement in hygiene- Improvement in hygiene

- improvement in sanitation- improvement in sanitation

- health education- health education

infectioninfection Sp. Sp.

InfectinInfectingg

humanhuman

Mode ofMode of

transmistransmissisi

InfectivInfective e

stagestage

Final Final

habitathabitatClinicalClinical

featuresfeatures

TricuriasisTricuriasis T.T.

trichuritrichuriaa

DirectDirect

FF

F/oralF/oral

Eggs Eggs CaecumCaecum

&&

AdjacenAdjacentt

BowelBowel

- Colitis- Colitis-Rectal prolapseRectal prolapse- Ectopic diseaseEctopic disease- growth growth retardationretardation

EntrobiasiEntrobiasiss

E.E.

vermicuvermicull

DirectDirect

F/oralF/oralEggsEggs CaecumCaecum

&&

AdjacenAdjacentt

BowelBowel

-Pruritus aniPruritus ani- pruritus vulvaepruritus vulvae- Ectopic disEctopic dis

Ascariasis Ascariasis A.A.

lumbriclumbricoioi

ModifiedModified

Direct Direct

F/oralF/oral

MatureMature

eggseggsSmallSmall

bowelbowel

-LofflersLofflers- Dyspepsia Dyspepsia - Under - Under nutritionnutrition- Obstructive Obstructive syndrsyndr

infectioninfection Sp.Sp.

InfectinInfectingg

humanhuman

Mode ofMode of

transmistransmisss

InfectiveInfective

stagestageFinalFinal

habitathabitatClinicalClinical

featuresfeatures

Hook Hook wormsworms

A. A. DuoDuodede

N. N. amamerieri

SkinSkin

penetratipenetratioo

FlariforFlariformm

larvaelarvae

SmallSmall

bowelbowel

- Ground itch Ground itch - Iron - Iron deficiency deficiency

anaemiaanaemia- DyspepsiaDyspepsia

--HypoalbuminaemHypoalbuminaemia ia

StrongloidStrongloidoo

Str.Str.

sterclaristerclariss

SkinSkin

penetratipenetratioo

FlariforFlariformm

larvaelarvae

SmallSmall

bowelbowel

- Lofflers Lofflers -Dyspepsia, diarrh Dyspepsia, diarrh - - MalabsorptionMalabsorption- Hyper infectionHyper infection

capillariascapillariasisis

CapCap

phillpinphillpinensisensis

IngestionIngestion

Of fishOf fishlarvaelarvae SmallSmall

bowelbowel- Malabsorption- Malabsorption

Drug therapy in nematodesDrug therapy in nematodes - Mebendazole 100 mg- Mebendazole 100 mg

- Albendazole 400 mg- Albendazole 400 mg

- Pyrental pamoate 100 mg/ kg ( 3 tabs)- Pyrental pamoate 100 mg/ kg ( 3 tabs)

- Oxantel 100 mg/kg- Oxantel 100 mg/kg

- Levamizole 3 tabs- Levamizole 3 tabs

- Thiabendazole 25 mg/kg- Thiabendazole 25 mg/kg

- Piperazine 100 mg/kg. 4 gm single dose- Piperazine 100 mg/kg. 4 gm single dose

- Ivermectin for strongloidosis- Ivermectin for strongloidosis

** Single doses of pyrental, oxantel or** Single doses of pyrental, oxantel or

albendazole is used for multiple albendazole is used for multiple infestationinfestation..