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{{Ancylostomiasis}}
{{Ancylostomiasis}}
{{CMG}} {{Kalpana Giri}}


{{CMG}} {{AE}} {{Kalpana Giri}}
==Overview==
==Overview==
[[Ancylostomiasis]] was first [[discovered]] by [[Dubini]], an [[Italian physician]], in 1838 who provided the first detailed description of [[hookworms]] during an [[autopsy]] on a woman who had died in Milan.
[[Ancylostomiasis]] is a [[hookworm infection]], [[soil-transmitted]] [[helminths]] (STH) occurs predominantly in [[countries]] with [[low socioeconomic]] [[status]] located in [[tropical]] and [[subtropical]] areas of the [[world]]. Common symptoms of ancylostomiasis include: [[anorexia]], [[flatulence]], [[diarrhea]], [[weight loss]], [[pallor]], [[dyspnea]], [[weakness]], [[generalized edema]], [[melena]], [[hematemesis]], [[dizziness]], [[syncope]], [[cough]], [[sneezing]], [[hemoptysis]], [[nausea]], [[vomiting]], [[pharyngeal irritation]], [[itchy]], [[erythematous]], [[serpiginous]] [[skin lesions]]. The mainstay of treatment for ancylostomiasis is [[anti-helminthic]] [[therapies]] are recommended among [[patients]] with [[ancylostomiasis]].


==Historical Perspective==
==Historical Perspective==
[[Ancylostomiasis]] was first [[discovered]] by [[Dubini]], an [[Italian physician]], in 1838 who provided the first detailed description of [[hookworms]] during an [[autopsy]] on a woman who had died in Milan. [[Necator americanus]] and [[Ancylostoma duodenale]] were responsible for all [[human]] [[hookworm]] [[infections]] mentioned by Bethony et al ( 2006), de Silva et al.(2003), however Bradbury & Traub (2016) and Traub et al. (2008) mentioned [[Ancylostoma ceylanicum]] is also an [[important]] [[hookworm]] of humans, especially in South East Asia.
[[Ancylostomiasis]] was first [[discovered]] by [[Dubini]], an [[Italian physician]], in 1838.


==Classification==
==Classification==
[[Ancylostomiasis]] may be classified according to the species into two groups: Human hookworm: [[Ancylostoma]] and [[Necator Americanus]] and Zoonotic hookworm: [[Ancylostoma braziliense]], [[Ancylostoma caninum]], [[Ancylostoma ceylanicum]] and [[Uncinaria stenocephala]].
[[Ancylostomiasis]] may be classified according to the species into two groups: Human hookworm: [[Ancylostoma]] and [[Necator Americanus]] and Zoonotic hookworm: [[Ancylostoma braziliense]], [[Ancylostoma caninum]], [[Ancylostoma ceylanicum]] and [[Uncinaria stenocephala]].


==pathophysiology==
==Pathophysiology==
[[Ancylostomiasis]] is a [[hookworm infection]], [[soil-transmitted]] [[helminths]] (STH) also known as [[miner's]] [[anaemia]], [[tunnel disease]], [[brickmaker's]] [[anaemia]] occurs predominantly in [[countries]] with [[low socioeconomic]] [[status]] located in [[tropical]] and [[subtropical]] areas of the [[world]]. The [[external]] [[surface]] of [[Helminth]] comprises key [[molecules]] [[excretory/secretory]] (ES) products which contain a large range of [[structurally]] and [[functionally]] distinct [[molecules]], mostly [[proteins]], and also [[lipids]], and [[carbohydrates]]. These [[molecules]] also have major functions in the development and survival of [[parasites]]. By inhibiting the [[inflammatory]] [[reaction]], [[encouraging]] [[effector cells]] [[apoptosis]], and [[skewing]] the [[immune reaction]] [[phenotype]], these [[molecules]] help the [[parasite]] to [[survive]] and evade the [[host]] [[immunological]] [[response]]. The [[biological]] [[role]] and [[molecular]] [[nature]] of [[hookworm]] ES products are still [[unclear]] though the [[intensive]] [[study]] has been done for many [[years]]. The life cycle of hookworm include: human hookworm and zoonotic hookworm. [[Mature females]] released eggs in the host’s [[small intestine]] and these eggs are passed in the feces, where they hatch [[first stage]] [[rhabditiform]] [[larva]] (L1) within several days. The L1 feeds on soil [[microbes]] and [[molts]] to the L2 stage, and under appropriate conditions, each eggs hatch in warm, moist, sandy soil, or in feces and develops into an [[infective]] [[filariform]] (L3) stage larva. The [[infective-stage]] [[larvae]] (L3) enter the body either through a [[cutaneous route]] or by [[direct]] [[oral ingestion]]. [[Human]] [[hookworm]] such as Ancylostoma and Necator Americanus enter the body by [[skin penetration]] which may cause a [[local pruritic]] [[dermatitis]], also called [[ground itch]] at the site of [[penetration]] whereas the [[ancylostoma species]] can also [[enter the body orally]]. The [[infective larvae]] (L3) [[migrate]] through the [[dermis]], enters the [[bloodstream]], and reach the [[lungs]] and [[migrate]] across the [[alveoli]]. Then they [[ascend]] from the [[bronchial tree]] to the [[pharynx]] and reach the [[small intestine]] where they [[mount]] into [[fourth-stage]] [[larvae]] and [[mature]] into [[blood-feeding]] [[adults]] [[male]] or [[female]]. These [[adult worms]] release [[hyaluronidase]] and other [[hydrolytic enzymes]] result in [[blood]] [[extravasation]] by degrading the [[intestinal mucosa]] and [[erosion]] of [[blood vessels]]. [[Hookworms]] also [[secrete]] [[Ancylostoma ceylanicum]] [[anticoagulant]] [[peptide-1]], which inhibits the [[blood]] [[coagulation]] in the [[attachment site]] and leads to [[blood loss]] from the [[intestine]]. [[Zoonotic]] [[hookworm]] (i.e., cat and dog hookworms) include: [[Ancylostoma braziliense]], [[Ancylostoma caninum]], [[Ancylostoma ceylanicum]] and [[Uncinaria stenocephala]]. Among these most commonly [[encountered]] [[hookworm]]is [[Ancylostoma braziliense]]. It causes [[cutaneous larva migrans]] ([[creeping eruption]]) [[generated]] by the [[larva migrating]] through the [[epidermis]] characterized by the [[erythematous serpiginous]] [[lesions]]. [[Ancylostoma ceylanicum]] is the only species that develops to [[adult]] in [[humans]], and causes [[enteric]] [[hookworm infection]]. [[Ancylostoma caninum]] occasionally reaches [[adulthood]] in [[humans]], and causes [[eosinophilic enteritis]].  
[[Ancylostomiasis]] is a [[hookworm infection]], [[soil-transmitted]] [[helminths]] (STH) occurs predominantly in [[countries]] with [[low socioeconomic]] [[status]] located in [[tropical]] and [[subtropical]] areas of the [[world]]. The life cycle of hookworm include: human hookworm and zoonotic hookworm. [[Mature females]] released eggs in the host’s [[small intestine]] and these eggs are passed in the feces. Under appropriate conditions, each eggs hatch in soil, and develops into an [[infective]] [[filariform]] (L3) stage larva. It enter the body either through a [[skin]] or [[oral ingestion]] then enters the [[bloodstream]], and reach the [[lungs]] and [[migrate]] across the [[alveoli]]. Then they [[ascend]] from the [[bronchial tree]] to the [[pharynx]] and reach the [[small intestine]] where they [[mount]] into [[fourth-stage]] [[larvae]] and [[mature]] into [[blood-feeding]] [[adults]] [[male]] or [[female]].


==Causes==
==Causes==
Common causes of [[Ancylostomiasis]] include: [[Ancylostoma duodenale]], [[Necator americanus]], [[Ancylostoma ceylanicum]], and less common organisms include: [[Ancylostoma braziliense]], [[Ancylostoma caninum]], [[Ancylostoma ceylanicum]], and [[Uncinaria stenocephala]].
Common causes of [[ancylostomiasis]] include: [[Ancylostoma duodenale]], [[Necator americanus]], [[Ancylostoma ceylanicum]], and less common organisms include: [[Ancylostoma braziliense]], [[Ancylostoma caninum]], [[Ancylostoma ceylanicum]], and [[Uncinaria stenocephala]].


==Differentiating ancylostomiasis from Other Diseases==
==Differentiating ancylostomiasis from Other Diseases==
[[Ancylostomiasis]] manifests in a variety of clinical forms, [[differentiation]] must be established in accordance with the particular sign and symptoms. Such as [[abdominal symptoms]] differentiated from [[ascariasis]] and [[trichuriasis]], and [[parasites]] associated with [[pneumonitis]] and [[peripheral eosinophilia]] are [[Aascaris]] and [[Strongyloides species]]. [[Cutaneous]] [[manifestations]] are [[differentiated]] from [[contact dermatitis]], [[scabies infection]], [[migratory myiasis]], and [[cercarial dermatitis]]. In infants [[gastrointestinal]] [[bleeding]]  must be [[differentiated]] from other diseases that cause [[melena]], [[pallor]], [[anorexia]], [[listlessness]], and [[edema]] such as [[portal hypertension]], [[Meckel’s diverticulum]], or [[AV malformation]]. In adults [[gastrointestinal bleeding]] must be differentiated from other [[diseases]] such as [[Meckel’s diverticulum]] and [[Dieulafoy’s lesions]], [[inflammatory bowel disease]] and [[nonsteroidal]] [[anti-inflammatory]] [[drug-induced]] [[small bowel disease]]. In older patient (>50 years old) are prone to [[gastrointestinal bleeding]] from [[angiectasias]], [[adenocarcinoma]], [[leiomyoma]], and [[lymphoma]].
[[Ancylostomiasis]] must be differentiated from [[contact dermatitis]], [[scabies infection]], [[migratory myiasis]], and [[cercarial dermatitis]] for [[cutaneous]] [[manifestations]], and [[portal hypertension]], [[meckel’s diverticulum]], [[inflammatory bowel disease]] and [[nonsteroidal]] [[anti-inflammatory]] [[drug-induced]] [[small bowel disease]], [[angiectasias]], [[adenocarcinoma]], [[leiomyoma]], and [[lymphoma]] for GI bleeding.


==Epidemiology and Demographics==
The [[incidence rate]] of [[hookworm]] infection was 7.5/100 person-years. Prevalence of [[ancylostomiasis]] is approximately 1 billion people worldwide. People of all ages are susceptible to [[ancylostomiasis]], commonly affects [[children]] and [[women]] of [[childbearing]] age. Mortality rate of [[hookworms]] in the [[tropics]] is approximately 50-60,000 deaths per year. Men are more [[commonly]] affected by [[ancylostomiasis]] than women.
== Risk Factors==
Common risk factors of ancylostomiasis include: [[exposure]] to [[soil]] where [[filariform larvae]], the [[infective stage]], live in and [[penetrate]] human [[skin]], [[poor sanitation]], [[low socioeconomic status]], [[low educational attainment]].
==Natural History, Complications, and Prognosis==
The majority of the [[infected]] [[patients]] remain [[asymptomatic]]. The symptoms of [[ancylostomiasis]] typically develop by [[direct contact]] of the [[skin]] with [[contaminated soil]] and the [[fecal-oral route]]. The most common complications include: [[iron deficiency anemia]], in child: [[intellectual]] and [[cognitive]] [[development]], in pregnant women: [[severe anemia]], [[impaired growth]], [[severe anemia]], [[premature birth]], [[neonatal anemia]]. Prognosis is generally [[excellent]] with [[proper treatment]].
==Diagnosis==
===Diagnostic Study of Choice===
The diagnostic test of [[ancylostomiasis]] is the [[microscopic]] [[detection]] of [[hookworms eggs]] in stool.
===History and Symptoms===
The majority of [[patients]] with [[ancylostomiasis]] are [[asymptomatic]]. Common symptoms of ancylostomiasis include: [[anorexia]], [[flatulence]], [[diarrhea]], [[weight loss]], [[pallor]], [[dyspnea]], [[weakness]], [[generalized edema]], [[melena]], [[hematemesis]], [[dizziness]], [[syncope]], [[cough]], [[sneezing]], [[hemoptysis]], [[nausea]], [[vomiting]], [[pharyngeal irritation]], [[itchy]], [[erythematous]], [[serpiginous]] [[skin lesions]].
===Physical examination===
Physical examination include: [[pallor]], [[fatigue]], [[dizziness]], [[serpiginous]], [[erythematous]], and [[palpable plaque]] associated with [[edema]], [[abdominal distension]].
===Lab Findings===
Lab findings include: decreased [[hemoglobin]], [[eosinophilia]], presence of several [[live and motile]] [[worms]] in [[upper gastrointestinal]] [[endoscopy]].
===X Ray===
There are no x-ray findings associated with ancylostomiasis.
===CT===
There are no CT findings associated with ancylostomiasis.
===Other Diagnostic Studies===
Other diagnostic studies for ancylostomiasis include [[upper gastrointestinal]] [[endoscopy]], which demonstrates [[live and motile]] [[worms]] in GI tract.
==Treatment==
===Medical Therapy===
[[Anti-helminthic]] [[therapies]] are recommended among [[patients]] with [[ancylostomiasis]]. [[Efficacy]] of [[treatment]] varies according to the [[severity]] of [[infection]], [[geographical]] [[distribution]], and [[age groups]]. [[Multiple blood transfusion]], [[iron supplements]] are also be given in severe cases.
===Surgery===
Surgical intervention is not recommended for the management of ancylostomiasis.
===Primary Prevention===
Effective measures for the primary prevention of ancylostomiasis include periodic mass anthelminthic treatment of at-risk populations, avoid gardening barefooted, patient education on [[proper hygiene]] and [[sanitation]].


==References==
==References==

Latest revision as of 22:39, 3 September 2021

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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Kalpana Giri, MBBS[2]

Overview

Ancylostomiasis is a hookworm infection, soil-transmitted helminths (STH) occurs predominantly in countries with low socioeconomic status located in tropical and subtropical areas of the world. Common symptoms of ancylostomiasis include: anorexia, flatulence, diarrhea, weight loss, pallor, dyspnea, weakness, generalized edema, melena, hematemesis, dizziness, syncope, cough, sneezing, hemoptysis, nausea, vomiting, pharyngeal irritation, itchy, erythematous, serpiginous skin lesions. The mainstay of treatment for ancylostomiasis is anti-helminthic therapies are recommended among patients with ancylostomiasis.

Historical Perspective

Ancylostomiasis was first discovered by Dubini, an Italian physician, in 1838.

Classification

Ancylostomiasis may be classified according to the species into two groups: Human hookworm: Ancylostoma and Necator Americanus and Zoonotic hookworm: Ancylostoma braziliense, Ancylostoma caninum, Ancylostoma ceylanicum and Uncinaria stenocephala.

Pathophysiology

Ancylostomiasis is a hookworm infection, soil-transmitted helminths (STH) occurs predominantly in countries with low socioeconomic status located in tropical and subtropical areas of the world. The life cycle of hookworm include: human hookworm and zoonotic hookworm. Mature females released eggs in the host’s small intestine and these eggs are passed in the feces. Under appropriate conditions, each eggs hatch in soil, and develops into an infective filariform (L3) stage larva. It enter the body either through a skin or oral ingestion then enters the bloodstream, and reach the lungs and migrate across the alveoli. Then they ascend from the bronchial tree to the pharynx and reach the small intestine where they mount into fourth-stage larvae and mature into blood-feeding adults male or female.

Causes

Common causes of ancylostomiasis include: Ancylostoma duodenale, Necator americanus, Ancylostoma ceylanicum, and less common organisms include: Ancylostoma braziliense, Ancylostoma caninum, Ancylostoma ceylanicum, and Uncinaria stenocephala.

Differentiating ancylostomiasis from Other Diseases

Ancylostomiasis must be differentiated from contact dermatitis, scabies infection, migratory myiasis, and cercarial dermatitis for cutaneous manifestations, and portal hypertension, meckel’s diverticulum, inflammatory bowel disease and nonsteroidal anti-inflammatory drug-induced small bowel disease, angiectasias, adenocarcinoma, leiomyoma, and lymphoma for GI bleeding.

Epidemiology and Demographics

The incidence rate of hookworm infection was 7.5/100 person-years. Prevalence of ancylostomiasis is approximately 1 billion people worldwide. People of all ages are susceptible to ancylostomiasis, commonly affects children and women of childbearing age. Mortality rate of hookworms in the tropics is approximately 50-60,000 deaths per year. Men are more commonly affected by ancylostomiasis than women.

Risk Factors

Common risk factors of ancylostomiasis include: exposure to soil where filariform larvae, the infective stage, live in and penetrate human skin, poor sanitation, low socioeconomic status, low educational attainment.

Natural History, Complications, and Prognosis

The majority of the infected patients remain asymptomatic. The symptoms of ancylostomiasis typically develop by direct contact of the skin with contaminated soil and the fecal-oral route. The most common complications include: iron deficiency anemia, in child: intellectual and cognitive development, in pregnant women: severe anemia, impaired growth, severe anemia, premature birth, neonatal anemia. Prognosis is generally excellent with proper treatment.

Diagnosis

Diagnostic Study of Choice

The diagnostic test of ancylostomiasis is the microscopic detection of hookworms eggs in stool.

History and Symptoms

The majority of patients with ancylostomiasis are asymptomatic. Common symptoms of ancylostomiasis include: anorexia, flatulence, diarrhea, weight loss, pallor, dyspnea, weakness, generalized edema, melena, hematemesis, dizziness, syncope, cough, sneezing, hemoptysis, nausea, vomiting, pharyngeal irritation, itchy, erythematous, serpiginous skin lesions.

Physical examination

Physical examination include: pallor, fatigue, dizziness, serpiginous, erythematous, and palpable plaque associated with edema, abdominal distension.

Lab Findings

Lab findings include: decreased hemoglobin, eosinophilia, presence of several live and motile worms in upper gastrointestinal endoscopy.

X Ray

There are no x-ray findings associated with ancylostomiasis.

CT

There are no CT findings associated with ancylostomiasis.

Other Diagnostic Studies

Other diagnostic studies for ancylostomiasis include upper gastrointestinal endoscopy, which demonstrates live and motile worms in GI tract.

Treatment

Medical Therapy

Anti-helminthic therapies are recommended among patients with ancylostomiasis. Efficacy of treatment varies according to the severity of infection, geographical distribution, and age groups. Multiple blood transfusion, iron supplements are also be given in severe cases.

Surgery

Surgical intervention is not recommended for the management of ancylostomiasis.

Primary Prevention

Effective measures for the primary prevention of ancylostomiasis include periodic mass anthelminthic treatment of at-risk populations, avoid gardening barefooted, patient education on proper hygiene and sanitation.

References

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