Hepatic and biliary ascariasis

Abdominal complications of ascariasis in childhood

OBJECTIVE

Complications of ascariasis are a significant cause of abdominal pain in pediatric emergencies, especially where it is endemic. A literature review was conducted with the aim of improving diagnostic and therapeutic approaches for these patients.

DATA SOURCES

A PubMed search was conducted using the key terms "ascariasis complications" and "hepatobiliary ascariasis". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, case reports, and reviews published up to December 2023.

SUMMARY OF FINDINGS

Obstruction of the small bowel is the most common complication. Others that are, rarer and more difficult to properly identify and treat, such as biliary, hepatic, and pancreatic complications, acute appendicitis, Meckel's diverticulitis, or peritoneal granulomas. Hepatic and pancreatic complications are rarer and more serious in children than in adults. While plain radiography is usually the only option in cases of intestinal obstruction, ultrasonography is the examination of choice in cases of hepatobiliary, pancreatic, and appendicular ascariasis complications in childhood. The treatment is clinical and conservative in most patients. Surgical treatment is indicated if conservative therapy fails, or if there are signs of complications. Laparoscopy has been used as an excellent technical alternative in adults with hepatobiliary complications of ascariasis, but further studies on its use in children are still needed.

CONCLUSION

The creation of protocols and greater debate on this subject should be encouraged for a better understanding of the disease and to establish an early diagnosis and adequate treatment for children with complications resulting from massive infestation by Ascaris lumbricoides.

Intestinal Helminths Infections as Infrequent Cause of Emergency Abdominal Surgery: A Retrospective Study in a University Hospital over 20 Years

INTRODUCTION

All organs of any organism can be affected by helminths. They can be seen in a broad spectrum, from simple infestations to extensive, life-threatening involvement. Symptomatology is usually of chronic latent course. However, sometimes the presentation is acute and requires urgent surgical intervention.

MATERIAL AND METHODS

We conducted a retrospective observational prospective recruitment study of patients undergoing emergency surgery for helminth infection from January 2000 to December 2019 at a university hospital. Sociodemographic and analytical variables, variables related to the clinical process, and the diagnostic test were analysed. Variables related to the surgical procedure and postoperative complications were also analysed.

RESULTS

A total of 36 patients required emergency surgery for their helminth infection, which represented 0.26% of emergency abdominal surgeries. The mean age was 34.91 ± 21.5 years, with a predominance of men (69.4%). Most patients presented with pain in the right iliac fossa (69.4%), followed by symptoms compatible with intestinal obstruction (19.4%). The most frequent surgical interventions were appendectomy (38.9%) followed bowel resection (33.3%) and ileocecal resection (11.1%). Enterobious vermicularis and Anisakis simplex both together accounted for 75% of the sample. Statistically significant differences were identified in age (p < 0.001), diagnostic test performed (p = 0.032), intraoperative clinical diagnosis (p = 0.005) and surgical treatment received (p < 0.001).

CONCLUSION

The frequency of emergency surgeries for intestinal helminth parasitism is decreasing. However, the majority of these are E. vermicularis and Anisakis simplex, which have distinctly different clinical presentations. Identification and recognition by physicians continue to be necessary for further postoperative management and possible complications.

Hepatobiliary Ascariasis in a Piglet

PURPOSE

Ascariasis caused by the helminth Ascaris suum is the most common parasitosis of swine worldwide and it may involve all age categories of pigs. The present study reports an unusual localization of A. suum worms in the biliary system of a piglet slaughtered for human consumption.

METHODS

The liver was subjected to ultrasound scan and pathological examination. The isolated worms were morphologically examined and the DNA was extracted for the molecular identification of the species involved.

RESULTS

A total of 43 preadult nematodes were found within the gallbladder and the bile ducts. Parasites were morphologically identified as belonging to the genus Ascaris and molecularly as A. suum. At gross examination, the liver was moderately enlarged, with the bile ducts severely dilated. A chronic inflammatory infiltrate was noted, often centered around ectatic bile ducts (up to 5 mm in diameter), lined by hyperplastic epithelium and filled with sections of nematodes. The worm sections showed smooth cuticle, coelomyarian musculature, and an intestinal tract lined by columnar, uninucleated cells within a pseudocoelom. The ex vivo ultrasonographic examination of the liver allowed the visualization of several nematodes in the bile duct lumen and could be suggested for in vivo diagnosis. Unfortunately, the absence of the intestine did not allow to define the pathogenesis of the infection.

CONCLUSION

Although, given the unusual nature of this finding, it is difficult to identify predisposing factors for this A. suum localization, it suggests that ascariasis should be considered in the differential diagnosis of pigs with hepatobiliary disease.

An update on the current and emerging pharmacotherapy for the treatment of human ascariasis

INTRODUCTION

Globally, Ascaris lumbricoides is the commonest helminthic infection that affects people in underdeveloped countries and returning immigrants in industrialized nations. This article aims to provide latest updates on the epidemiology, clinical manifestations, and pharmacotherapy of ascariasis.

AREAS COVERED

A PubMed search was conducted using Clinical Queries and the key terms 'human ascariasis' OR 'Ascaris lumbricoides.' Ascaris lumbricoides is highly endemic in tropical and subtropic regions and among returning immigrants in industrialized nations. Predisposing factors include poor sanitation and poverty. The prevalence is greatest in young children. Most infected patients are asymptomatic. Patients with A. lumbricoides infection should be treated with anti-helminthic drugs to prevent complications from migration of the worm. Mebendazole and albendazole are indicated for children and nonpregnant women. Pregnant individuals should be treated with pyrantel pamoate.

EXPERT OPINION

Cure rates with anthelmintic treatment are high. No emerging pharmacotherapy can replace these existing drugs of good efficacy, safety profile and low cost for public health. It is opinioned that advances in the management of ascariasis include diagnostic accuracy at affordable costs, Emodepside is highly effective in single doses against ascarids in mammals and in human trials. The drug could be registered for human use in multiple neglected tropical diseases.

My 40-Year Encounter with ERCP: A Saga of Service, Syndromes, and Solutions

Endoscopic retrograde cholangiopancreatography (ERCP) has been a significant development in gastrointestinal endoscopy. I did my first ERCP at SKIMS on December 5, 1982, and over the last 40 years, I have performed 10,100 ERCP procedures, including 600 Sphincter of Oddi manometries (SOM), and 3200 therapeutic ERCPs. We were confronted with many clinical challenges that needed answers by applying ERCP as a primary diagnostic tool. These studies gave birth to and/or recognition of several clinical syndromes. The hepatobiliary and pancreatic ascariasis (HBPA) as a clinical disease was recognized in 1985. The nematode, Ascaris lumbricoides, was the most common cause of hepatobiliary and pancreatic diseases in Kashmir, and its impact on healthcare, clinical profile, management policies, and control measures was identified. Kashmir was recognized as an endemic zone for recurrent pyogenic cholangitis (RPC), which constituted 12.5% of all biliary diseases. RPC in this population was found essentially to be an aftermath of HBPA. A subset of patients with hepatic hydatidosis with rupture into the biliary tract was recognized at ERCP and primarily treated by endotherapy. Cholangiographic abnormalities in children with portal cavernoma evolved into the recognition of portal biliopathy. Extensive studies of the sphincter of Oddi manometry in patients with unexplained biliary and/or pancreatic pain following cholecystectomy identified the entity of the sphincter of Oddi dyskinesia (SOD). In a cross-over trial, Nifedipine, compared with a placebo, showed a significant clinical response in 20 of 28 such patients. ERCP studies done in patients with tropical calcific pancreatitis showed an anomalous union of bile and pancreatic ducts. Forty of the 220 patients with liver transplantation had biliary complications namely biliary leaks, bile duct strictures, SOD, and recurrence of underlying primary biliary cholangitis. Biliary complications caused considerable morbidity and mortality in patients with liver transplantation.

An unusual finding: Biliary ascariasis in a pregnant patient managed conservatively-a case report

Introduction and importance

Biliary ascariasis, caused by Ascaris lumbricoides, is a rare condition, especially in non-endemic areas. However, it can present with complications such as biliary obstruction, requiring prompt diagnosis and management. This case report highlights the incidental detection and successful management of biliary ascariasis in a pregnant patient.

Case presentation

A 26-year-old primigravida woman at 24 weeks gestation presented with mild icterus, anorexia, and gastrointestinal symptoms. Laboratory tests showed elevated bilirubin levels and peripheral eosinophilia. Abdominal ultrasound revealed the presence of roundworms in the gallbladder and common bile duct. The patient was managed conservatively with an anti-helminthic agent, resulting in the passing of a dead worm and the resolution of symptoms.

Clinical discussion

Biliary ascariasis is a rare condition in non-endemic areas but should be considered in pregnant patients presenting with biliary symptoms. Prompt diagnosis is crucial, and imaging modalities such as abdominal ultrasound play a vital role. Conservative management with appropriate anti-helminthic therapy can effectively resolve symptoms and eliminate the infection.

Conclusion

This case report emphasizes the importance of considering biliary ascariasis in pregnant patients with biliary symptoms. Timely diagnosis, utilizing imaging modalities, and initiating conservative management with anti-helminthic therapy can lead to successful treatment outcomes. Increased awareness and understanding of this condition can aid clinicians in providing optimal care to similar patients.

Biliary ascariasis misidentified as a biliary stent in a patient undergoing liver resection

Ascaris lumbricoides causes one of the most common soil-transmitted helminthiases globally. The worms mostly infect the human small intestine and elicit negligible or nonspecific symptoms, but there are reports of extraintestinal ectopic ascariasis. We describe a rare case of biliary ascariasis mistaken for biliary stent in a 72-year-old female patient with a history of liver resection. She visited our outpatient clinic complaining of right upper quadrant pain and fever for the past week. She had previously undergone left lateral sectionectomy for recurrent biliary and intrahepatic duct stones 2 years ago. Besides mildly elevated gamma-glutamyl transferase levels, her liver function tests were normal. Magnetic resonance cholangiopancreatography revealed a linear filling defect closely resembling an internal stent from the common bile duct to the right intrahepatic bile duct. A live female A. lumbricoides adult worm was removed by endoscopic retrograde cholangiopancreatography (ERCP). Despite a significant decrease of the ascariasis prevalence in Korea, cases of biliary ascariasis are still occasionally reported. In this study, a additional case of biliary ascariasis, which was radiologically misdiagnosed as the biliary stent, was described in a hepatic resection patient by the worm recovery with ERCP in Korea.

A Case Report on Biliary Ascariasis

Biliary Ascariasis occurs when Ascaris lumbricoides worms invade the biliary system. It may cause biliary obstruction, cholangitis, cholecystitis, or acute pancreatitis. We report a case of a 37-year-old female patient who presented with a history of upper abdominal pain, nausea, vomiting, and weight loss for two weeks. Ultrasound showed dilated common bile duct with linear tubular echogenic structure in the common bile duct and bowel loops. Endoscopic Retrograde Cholangio pancreatography (ERCP) revealed large adult worms confirming the diagnosis of Ascariasis.

Diagnosis of Asymptomatic Biliary Ascariasis by Abdominal Ultrasound in a Non-Endemic Area

Biliary ascariasis is rare in non-endemic areas. This infection is associated with severe complications of the biliary tract, which can become a medical emergency. Treatment with oral anthelmintics is often effective, but, in some cases, surgery is required.  We describe an unusual case of ultrasound diagnosis of biliary ascariasis in the gallbladder in a patient who, besides residing in a low-prevalence area of the infection, did not present with biliary tract manifestations. We intend to raise awareness of this clinical entity in non-endemic areas, where this diagnosis is not usually considered. A brief review of the subject is also presented.

Successful Management of Biliary Ascariasis in a High-Endemic Zone and Low-Resource Setting in Ethiopia

Ascariasis lumbricoides is a roundworm that causes one of the most common soil-transmitted helminth infections worldwide. Ascariasis is typically found in the jejunum and transmitted through the intake of Ascaris lumbricoides eggs through food and water. Initially, ascariasis can cause pulmonary symptoms during the first 6-8 weeks of ingestion and can progress to serious complications of intestinal obstruction and hepatobiliary manifestations. Biliary ascariasis is a complication of ascariasis migration from the jejunum to the hepatobiliary tree and can present with a variety of symptoms ranging from biliary colic to more serious features such as acute cholangitis. Though the mortality rate is low, limited resources for management can make it challenging to manage.

Hepatobiliary and Pancreatic Duct Ascariasis: An Unusual Cause of Obstructive Jaundice and Severe Acute Cholangitis

Introduction

Acute cholangitis caused by hepatobiliary ascariasis is quite rare. Factors like a prior history of hepatobiliary surgery, pregnancy, and prolonged fasting increase the possibility of developing hepatobiliary ascariasis.

Case Presentation

We present a case of obstructive jaundice and severe acute cholangitis caused by massive hepatobiliary and pancreatic duct ascariasis in a 52-year-old male patient. The diagnosis was made based on clinical presentation, imaging, and other basic investigations. The treatment consisted of conservative medical treatment, without an anti-helminthic drug to avoid the death of the worm inside the bile duct with subsequent complications. Our patient declined surgical treatment and died three days after self-discharge.

Conclusion

Ascaris lumbricoides is a uncommon cause of acute cholangitis. It should be suspected in cases with typical clinical presentation and imaging evidence suggestive of hepatobiliary ascariasis. Endoscopic treatment is the treatment of choice in addition to anti-helminthic drugs and additional medical support. Conservative treatment alone is less likely to be successful.

[Ascaris lumbricoides-induced pancreatic lesion]

Ascaris lumbricoides is nematode localized in human small bowel in most cases. This nematode is capable for migration. Pancreatitis is one of the most common surgical diseases. One of the causes of this pancreatitis may be migration of Ascaris lumbricoides from small bowel through the major duodenal papilla to the pancreatic ducts. This migration is provided by complex of morphological and functional disorders of digestive system associated with this helminthiasis, as well as certain risk factors. These are previous cholecystectomy, sphincterotomy, living in endemic areas, massive Ascaris lumbricoides invasion, pregnancy. Damage of the pancreas develops due to direct mechanical effect of nematodes and allergic reactions, papillitis and functional disorders of digestive tract. Pancreatitis is usually mild, but severe course of disease is also possible. A typical symptom of pancreatitis caused by Ascaris lumbricoides is helminths in vomit and/or feces.

Successful Conservative Management of Uncomplicated Gallbladder Ascariasis

Ascariasis is one of the common diseases in human beings worldwide. Most cases are asymptomatic. However, the high parasitic load can present with organ-specific symptoms due to the migration of worms to various regions of the body such as the lungs, nasal cavity, oral cavity, and biliary system, and sometimes with surgical emergencies like intestinal and biliary tree obstruction. Treatment modalities depend on the presentation and the complication associated with it. Uncomplicated cases can be initially managed conservatively and followed up subsequently. However, most cases of biliary ascariasis may require surgical intervention or endoscopic management due to failed management or complications. We report a case of a young male with gallbladder ascariasis diagnosed with ultrasonography and successfully treated with a single dose of albendazole 400 mg. Follow-up ultrasonography was done to evaluate the management.

Endoscopic management of biliary ascariasis: A case report

BACKGROUND

Biliary ascariasis is rare but remains the most common parasitic infection in remote areas and in people with poor medical conditions. Here, we reported a case of biliary ascariasis in order to raise awareness of possible parasitic infections.

CASE SUMMARY

A 68-year-old female was admitted to the emergency room of the Affiliated Hospital of Guizhou Medical University on 28 September 2017, with chief complaint of pain in the right upper abdomen. Ultrasonography of the abdomen showed that the upper segment of the common bile duct was slightly dilated with parallel tubular structures, indicative of biliary ascariasis. Endoscopic retrograde cholangiopancreatography was performed under general anesthesia on 29 September 2017, and an adult Ascaris lumbricoides worm was observed. After the worm was removed from the bile duct, the patient’s pain immediately subsided. The patient was successfully cured, without any complications.

CONCLUSION

This report emphasizes the need for physicians to consider biliary ascariasis as a possible cause when treating cases of biliary colic.

Massive biliary ascariasis: an unusual cause of acute cholangitis

Acute cholangitis is a condition of bacterial infection following hepatobiliary tract obstruction, which signifies poor prognosis unless adequately drained. The most common cause of bile duct obstruction is choledocholithiasis, in contrast to parasitic infestation, a rare entity causing acute cholangitis nowadays. Therefore, we reported the case of a 68-year-old Thai man who presented with acute fever, intense right upper quadrant abdominal pain and jaundice for 2 days. His medical history was normal except for the history of intermittent biliary colic for a year. Endoscopic retrograde cholangiography was performed and demonstrated multiple, creamy-coloured roundworms coming out from the ampulla of Vater as well as a tubular filling defect in dilated common bile duct from cholangiography. He was diagnosed with acute cholangitis by biliary ascariasis and underwent endoscopic parasitic removal, which subsequently improved symptoms.

Treatment response and long-term outcomes in biliary ascariasis: A prospective study

BACKGROUND AND STUDY AIMS

Anti-helminthic therapy and endoscopic worm extraction had variable success rates in biliary ascariasis. Recurrent biliary events after worm clearance are common. We aimed to evaluate the outcomes of management in biliary ascariasis and find out the incidence and risk factors for the development of recurrent biliary events.

PATIENTS AND METHODS

Consecutive patients with biliary ascariasis detected on abdominal ultrasound (AUS), were selected. Initial conservative treatment with oral Albendazole (400 mg) and analgesics was started in all. Successful therapy was defined as symptomatic resolution, and AUS confirmed biliary clearance after three weeks. ERCP (Endoscopic retrograde cholangiopancreatography) was performed in patients with failed conservative management. The patients were prospectively followed up for a minimum period of 1 year.

RESULTS

Among 98 patients with biliary ascariasis, 23 (23.5%) responded to medical management alone. A presentation with obstructive jaundice (p = 0.04) and cholangitis (p = 0.007) was significantly associated with failure to medical management. Sixty-five (86.7%) among 75 patients had successful biliary clearance with ERCP. During a median follow up of 16 months, 24 (24.5%) patients had recurrent biliary events. Lower socioeconomic status (OR = 0.78, p = 0.023) and longer follow-up (OR = 1.16, p = 0.001) were independent risk factors for recurrent biliary events.

CONCLUSION

Early ERCP among high-risk patients and proper hygiene are the keys to successful management in biliary ascariasis.

Expression of Ascaris lumbricoides putative virulence-associated genes when infecting a human host

BACKGROUND

Ascaris lumbricoides is the most common causative agent of soil-transmitted helminth infections worldwide, with an estimated 450 million people infected with this nematode globally. It is suggested that helminths are capable of evading and manipulating the host immune system through the release of a spectrum of worm proteins which underpins their long-term survival in the host. We hypothesise that the worm overexpresses these proteins when infecting adults compared to children to cirvumvent the more robust defence mechanisms of adults. However, little is known about the parasite's genes and encoded proteins involved during A. lumbricoides infection. Hence, this study was conducted to assess the expression profile of putative virulence-associated genes during an active infection of adults and children.

METHODS

In this study, quantitative PCR was performed to evaluate the expression profile of putative virulence-associated genes in A. lumbricoides isolated from infected children and adults. The study was initiated by collecting adult worms expelled from adults and children following anthelminthic treatment. High-quality RNA was successfully extracted from each of six adult worms expelled by three adults and three children, respectively. Eleven putative homologues of helminth virulence-associated genes reported in previous studies were selected, primers were designed and specific amplicons of A. lumbricoides genes were noted. The expression profiles of these putative virulence-associated genes in A. lumbricoides from infected adults were compared to those in A. lumbricoides from infected children.

RESULTS

The putative virulence-associated genes VENOM, CADHERIN and PEBP were significantly upregulated at 166-fold, 13-fold and fivefold, respectively, in adults compared to children. Conversely, the transcription of ABA-1 (fourfold), CATH-L (threefold) and INTEGRIN (twofold) was significantly suppressed in A. lumbricoides from infected adults.

CONCLUSIONS

On the basis of the expression profile of the putative virulence-associated genes, we propose that the encoded proteins have potential roles in evasion mechanisms, which could guide the development of therapeutic interventions.

Typical imaging finding of hepatic infections: a pictorial essay

Hepatic infections are frequent in clinical practice. Although epidemiological, clinical and laboratory data may suggest hepatic infection in certain cases, imaging is nearly always necessary to confirm the diagnosis, assess disease extension and its complications, evaluate the response to treatment, and sometimes to make differential diagnoses such as malignancies. Ultrasound (US) is usually the first-line investigation, while computed tomography (CT) and magnetic resonance imaging (MRI) provide better characterization and a more precise assessment of local extension, especially biliary and vascular. The purpose of this article is to describe the typical features and main complications of common hepatic infections. Familiarity with the radiological features of this entity can help suggest the correct diagnosis and the need for further studies as well as determine appropriate and timely treatment.

Ascariasis and Cardiac Surgery: A Case Report

Ascariasis is a common helminthic infection, particularly in the tropical countries. We describe a case of eosinophilia who underwent coronary artery bypass graft (CABG) surgery. Postoperatively, he was found to have ascaris lumbricoides in the oral cavity. Timely detection and removal of the worm prevented the possible complications such as airway obstruction, bronchospasm, lung collapse, or intestinal obstruction. The case emphasizes the importance of considering parasitic infection as a differential diagnosis in patients presenting with eosinophilia for elective surgery.

Human Ascariasis: An Updated Review

Background:

Ascaris lumbricoides is the most common helminthic infection. More than 1.2 billion people have ascariasis worldwide.

Objective:

This article aimed to provide an update on the evaluation, diagnosis, and treatment of ascariasis.

Methods:

A PubMed search was conducted in February 2020 in Clinical Queries using the key terms “ascariasis” OR “Ascaris lumbricoides”. The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews published within the past 10 years. The search was restricted to English literature. The information retrieved from the above search was used in the compilation of the present article. Patents were searched using the key term “ascariasis” OR “Ascaris lumbricoides” in www.freepatentsonline.com.

Results:

Ascaris lumbricoides is transmitted through the ingestion of embryonated eggs from fecal- contaminated material. Ascariasis has high endemicity in tropical and subtropical areas. Predisposing factors include poverty, poor sanitation, inadequate sewage disposal, and poor personal hygiene. The prevalence is greatest in children younger than 5 years of age. The majority of patients with intestinal ascariasis are asymptomatic. For those with symptoms, anorexia, nausea, bloating, abdominal discomfort, recurrent abdominal pain, abdominal distension, and intermittent diarrhea are not uncommon. Other clinical manifestations vary widely, depending on the underlying complications. Complications include Löeffler syndrome, intestinal obstruction, biliary colic, recurrent pyogenic cholangitis, cholecystitis, acalculous cholecystitis, obstructive jaundice, cholelithiasis, pancreatitis, and malnutrition. The diagnosis is best established by microscopic examination of fecal smears or following concentration techniques for the characteristic ova. Patients with A. lumbricoides infection warrant anthelminthic treatment, even if they are asymptomatic, to prevent complications from migration of the parasite. Albendazole and mebendazole are the drugs of choice for children and nonpregnant individuals with ascariasis. Pregnant women with ascariasis should be treated with pyrantel pamoate. Recent patents related to the management of ascariasis are also discussed.

Conclusion:

The average cure rate with anthelminthic treatment is over 95%. Unfortunately, most treated patients in endemic areas become re-infected within months. Health education, personal hygiene, improved sanitary conditions, proper disposal of human excreta, and discontinuing the use of human fecal matter as a fertilizer are effective long-term preventive measures. Targeting deworming treatment and mass anthelminthic treatment should be considered in regions where A. lumbricoides is prevalent.

Ascaris-mimicking common bile duct stone: A case report

BACKGROUND

In most cases, it is not difficult to differentiate common bile duct (CBD) stone from Ascaris infection because they are different disease entities and have different imaging findings. The two diseases usually demonstrate unique characteristic findings on computed tomography or magnetic resonance cholangiopancreatography. However, we report a rare case from our experience in which a CBD stone mimicked and was misdiagnosed as Ascaris.

CASE SUMMARY

A 72-year-old male presented with elevated serum liver enzymes. Computed tomography showed a hyper-attenuated, elongated lesion in the CBD lumen and associated biliary inflammation. Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography revealed a linear filling defect in the bile duct. Moreover, elongated echogenic material with a central hypoechogenic area was seen on endoscopic ultrasound. Although the imaging findings caused us to suspect infection with the nematode Ascaris, the lesion was revealed to be a dark-brown-colored CBD stone through endoscopic extraction.

CONCLUSION

We report a rare case of a CBD stone that mimicked Ascaris. We also review the literature for side-by-side comparisons of the imaging features of CBD stones and ascariasis.

Whipworm and roundworm infections

Trichuriasis and ascariasis are neglected tropical diseases caused by the gastrointestinal dwelling nematodes Trichuris trichiura (a whipworm) and Ascaris lumbricoides (a roundworm), respectively. Both parasites are staggeringly prevalent, particularly in tropical and subtropical areas, and are associated with substantial morbidity. Infection is initiated by ingestion of infective eggs, which hatch in the intestine. Thereafter, T. trichiura larvae moult within intestinal epithelial cells, with adult worms embedded in a partially intracellular niche in the large intestine, whereas A. lumbricoides larvae penetrate the gut mucosa and migrate through the liver and lungs before returning to the lumen of the small intestine, where adult worms dwell. Both species elicit type 2 anti-parasite immunity. Diagnosis is typically based on clinical presentation (gastrointestinal symptoms and inflammation) and the detection of eggs or parasite DNA in the faeces. Prevention and treatment strategies rely on periodic mass drug administration (generally with albendazole or mebendazole) to at-risk populations and improvements in water, sanitation and hygiene. The effectiveness of drug treatment is very high for A. lumbricoides infections, whereas cure rates for T. trichiura infections are low. Novel anthelminthic drugs are needed, together with vaccine development and tools for diagnosis and assessment of parasite control in the field.

Biliary ascariasis and severe bacterial outcomes: Report of three cases from a paediatric hospital in Brazil

INTRODUCTION

Biliary ascariasis, although uncommon, can lead to infectious complications and severe outcomes. This study reported three patients with biliary ascariasis and who were admitted to a paediatric hospital in Salvador, Brazil.

CASE REPORTS

Case 1: A 1-year-old boy, with HIV, hospitalised with diarrhoea, fever, pain, and abdominal distension. He underwent an exploratory laparotomy, which showed peritonitis secondary to a perforation of the hepatic duct by ascaris. Case 2: A 3-year-old boy admitted with fever, abdominal pain and jaundice. Imaging examination was suggestive of ascaris in the intrahepatic biliary tract and a hepatic abscess. Case 3: A 7-year-old boy who was hospitalised with a history of abdominal colic, jaundice and fever, with a suggestive image of ascaris in the biliary tract and evolution to sepsis.

DISCUSSION

Three cases of biliary ascariasis were reported with severe infectious complications involving peritonitis, hepatic abscess and sepsis.

CONCLUSION

In endemic regions, biliary ascariasis should be considered in cases with jaundice, abdominal pain and fever, due to its morbidity and risk of complications.

Prevalence of Intestinal Parasitic Infections among the Bulgarian Population Over a Three Year Period (2015 - 2017)

The aim of the present study is to perform a retrospective analysis of the prevalence of intestinal parasitic infections among the Bulgarian population over the period 2015 - 2017. The study involved all Bulgarians and foreign nationals residing in the country who had been tested for intestinal protozoa and helminths. A total of 23,785 infections have been revealed, of which 17,712 (74.47 %) were helminth and 6,073 (25.53 %) protozoan invasions. Enterobiasis was found to be the most prevalent among patients infected with intestinal helminths (81.75 %), while giardiasis (62.05 %) was the most common among those diagnosed with protozoan infections. In spite of improved living conditions and increasing public health awareness, parasitic diseases in general, and intestinal parasitic infections in particular, still represent a significant part of the overall morbidity in Bulgaria, thus posing a major issue for the public health care system.

Not everything in the gallbladder is gallstones: an unusual case of biliary ascariasis

A 25-year-old female presented with a sore throat, fever and epigastric pain after coming from India. She had an obstructive pattern of liver function tests and an ultrasound scan abdomen showed features suggestive of acute cholecystitis and pancreatitis, with no obvious gallstones. She made no improvement with intravenous antibiotics. Subsequently, a contrast CT demonstrated a curvilinear structure within a thickened gallbladder and common bile duct. After input from multiple specialities, she had a MR cholangiopancreatography (MRCP) which further confirmed the curvilinear filling defect impacted in the gallbladder neck and proximal common bile duct. Biliary ascariasis with mild pancreatitis was diagnosed and was successfully treated with mebendazole. At one-month outpatient follow-up, her liver function tests and ultrasound scan had returned to normal. This case report discusses the radiological findings seen with biliary ascariasis using a range of imaging modalities. It also highlights the importance of the multidisciplinary team in managing a patient who presents a diagnostic challenge, in order to achieve the best patient outcome.

An unusual finding of obstructive jaundice—a case report and review of the literature

Biliary ascariasis is a tropical infectious disease, endemic in regions such as the Far East, Indian subcontinent and parts of the Middle East. The responsible organism is the Ascaris lumbricoides worm. This case study presents a 54-year-old British Caucasian female patient, admitted with a 1-week history of generalized abdominal pain. Ultrasound scan of the abdomen showed a collapsed and abnormal image of the gallbladder. Further imaging for better visualization by magnetic resonance cholangiography showed a 6 cm linear structure in the gallbladder. The morphology was characteristic of gallbladder ascariasis. Detailed history revealed that 6 months ago she had travelled to Turkey. Stool cultures confirmed the presence of ascaris eggs. She was treated conservatively with a 500 mg stat dose of Mebendazole. She was followed up in 6 weeks showing complete resolution of her symptoms.

Ascaridial Volvulus: An Uncommon Cause of Ileal Perforation

Ascariasis is a common worm infestation in developing and under-developed countries. It is caused by the ingestion of food contaminated with Ascaris eggs from faeces and is more common in places with poor sanitation. Almost 25% of the world population is infested by Ascaris lumbricoides. Although ascariasis is a chronic disease, it can present as acute abdomen rarely. The wandering nature of Ascaris in and out of the bowel causes various abdominal complications such as intestinal obstruction, perforation, biliary ascariasis, pancreatic ascariasis, liver abscess, appendicitis, and Meckel's diverticulitis. Intestinal obstruction is the most common complication seen in children and is usually due to mechanical bowel obstruction, volvulus or intussusception. Mechanical obstruction by a bolus of worms is the most common cause of bowel obstruction. Perforation of bowel is rarely reported and it usually occurs in the diseased segment of bowel or following trauma. Perforation of an ileal volvulus secondary to ascariasis has been reported rarely. We present a 4-year-old boy who presented to the emergency room with features of bowel perforation and sepsis, after unsuccessful management for intestinal obstruction in another hospital. On laparotomy, the small bowel was teaming with Ascaris worms. Ileum showed a volvulus with closed loop obstruction and perforation. Peritoneal lavage with resection and ileostomy was done, which was closed at a later date. Anti-helminthic agents were started postoperatively and the boy recovered uneventfully.

Soil-transmitted helminth infections

More than a quarter of the world's population is at risk of infection with the soil-transmitted helminths Ascaris lumbricoides, hookworm (Ancylostoma duodenale and Necator americanus), Trichuris trichiura, and Strongyloides stercoralis. Infected children and adults present with a range of medical and surgical conditions, and clinicians should consider the possibility of infection in individuals living in, or returning from, endemic regions. Although safe and effective drugs are donated free to endemic countries, only half of at-risk children received treatment in 2016. This Seminar describes the epidemiology, lifecycles, pathophysiology, clinical diagnosis, management, and public health control of soil-transmitted helminths. Previous work has questioned the effect of population-level deworming; however, it remains beyond doubt that treatment reduces the severe consequences of soil-transmitted helminthiasis. We highlight the need for refined diagnostic tools and effective control options to scale up public health interventions and improve clinical detection and management of these infections.

Gallbladder ascariasis in Kosovo - focus on ultrasound and conservative therapy: a case series

BACKGROUND

Ascaris lumbricoides is one of the most common intestinal infections in developing countries, including Kosovo. In contrast to migration to the bile duct, migration of the worm to the gallbladder, due to the narrow and tortuous nature of the cystic duct, is rare. When it does occur, it incites acalculous cholecystitis.

CASE PRESENTATIONS

This case series describes a 16-month-old Albanian girl, a 22-month-old Albanian girl, a 4-year-old Albanian girl, and a 10-year-old Albanian boy. Here we report our experience with gallbladder ascariasis including clinical manifestations, diagnostic procedures, and treatment. Fever, diarrhea and vomiting, dehydration, pale appearance, and weakness were the manifestations of the primary disease. In all patients, a physical examination revealed reduced turgor and elasticity of the skin. Abdomen was at the level of the chest, soft, with minimal palpatory pain. The liver and spleen were not palpable. A laboratory examination was not specific except for eosinophilia. There were no pathogenic bacteria in coproculture but Ascaris was found in all patients. At an ultrasound examination in all cases we found single, long, linear echogenic structure without acoustic shadowing containing a central, longitudinal anechoic tube with characteristic movement within the gallbladder. Edema of the gallbladder wall was suggestive of associated inflammation. There were no other findings on adjacent structures and organs. All patients received mebendazole 100 mg twice a day for 3 days. They also received symptomatic therapy for gastroenteritis. Because of elevated markers of inflammation all patients were treated with antibiotics, assuming acute cholecystitis, although ultrasound was able to confirm cholecystitis in only two of our four patients. Since the length of stay was dependent on the primary pathology it was 7 to 10 days. At control ultrasounds on 14th day, third and sixth month, all patients were free of ascariasis.

CONCLUSIONS

Gallbladder ascariasis should be considered in all patients presenting with abdominal pain, distension, colic, nausea, anorexia, and intermittent diarrhea associated with jaundice, nausea, vomiting, fever, and severe radiating pain. Eosinophilia, ova, and parasites on stool examination as well as an anechogenic tube with characteristic movement within the bile duct found on abdominal ultrasound are conclusive for diagnosis. Mebendazole is an effective drug for the treatment. Surgical treatment is rarely needed.

A Case of Biliary Ascariasis in Korea

Biliary ascariasis is still the leading cause of surgical complication of ascariasis, though its incidence has been dramatically reduced. Herein, we report a case of biliary ascariasis for the purpose of enhancing awareness of parasitic infections as a possible cause. A 72-year-old male visited the emergency room of Dankook University Hospital on 12 July 2015, complaining of right-upper-quadrant pain. By endoscopic retrograde cholangiopancreatography (ERCP), a tubular filling defect in the right hepatic duct was detected. The defect was endoscopically removed and diagnosed as an adult female of Ascaris lumbricoides worm, of 30 cm length. Upon removal of the worm, the pain subsided, and the patient was discharged without any complication. When treating cases of biliary colic, physicians should not neglect biliary ascariasis as the possible cause.

Enterobius vermicularis presentation during laparoscopic cholecystectomy

Enterobius vermicularis infection is uncommon in adults, compared to children, and rarely causes significant illness. Adult infection is usually colonic in nature and found incidentally at colonoscopy. Worm migration to other tissues is rare. We here-in describe the case of a 73-year-old woman found to have biliary tree E. vermicularis—an as yet undescribed site of migration.

Epidemiology and geographical distribution of gastrointestinal parasitic infection in humans in Slovakia

Examinations of the set of 2,760 samples of human stools revealed the current epidemiological situation in the occurrence of gastrointestinal parasitoses in Slovakia. Prevalence of gastrointestinal parasitic infection was P = 6.81 % out of which the protozoan infections was P = 2.64 % and helminthiases P = 4.17 %, in the representation of endoparasitic species Entamoeba coli, Giardia intestinalis, Blastocystis hominis, Endolimax nana, Ascaris lumbricoides, Trichuris trichiura and Enterobius vermicularis.

The species with the highest proportion from the protozoa was Entamoeba coli (P = 0.79 %) and from the helminths Ascaris lumbricoides (P = 3.73 %). The highest prevalence of protozoan infections (P = 3.27 %) was found in the age group 8 – 18 yearly and helminthic infections (P = 5.84 %) in the lowest age group of children at the age of 1 month to 7 years. Almost regularly, there was most frequently infection with Endolimax nana, Giardia intestinalis and Ascaris lumbricoides. By comparison of all age categories, a high statistical significance of differences in the prevalence of helminthiases was found, which most frequently infected children aged from 1 month to 7 years (X2, p≤ 0.0001). The statistical significance of differences in the incidence of protozoan infections (X2, p≤ 0.01) and helminthiases (X2, p≤ 0.0001) was recorded between the compared regions of Slovakia (Western, Central and Eastern Slovakia) with the highest prevalence in the eastern region of Slovakia.

Parasitic and infectious diseases of the biliary tract in migrants and international travelers

In recent years, global and regional crises have led to extraordinary worldwide migration, accompanied by an increase in long-distance travel from Western countries. Both are linked to a rising incidence of rare parasitic and infectious diseases in first world countries, including in the biliary tract. Areas covered: A selective literature research in PubMed was performed to review the most important parasitic and infectious biliary diseases, which are caused by a wide variety of pathogens and may be latent over long periods, with chronic courses leading to cholangitis, hepatic failure or development of cholangiocarcinoma. Parasites such as Ascaris, Fasciola and Clonorchis/Opisthorchis are particularly important and may trigger biliary diseases or predisposition for bacterial superinfections. Viral or protozoal cholangitis is mainly a problem of impaired immunity. Expert commentary: Currently, these entities are still rare in migrants and long-distance travelers. However, a significant increase in Western countries has to be expected. Incidences are most likely underestimated because of protracted clinical latency. Diagnosis depends on the relevant pathogens, the host's immune status and the extent or distribution of biliary obstruction. Modern tomographic methods, ERCP and specific microbiological/parasitological/virological tests are of crucial diagnostic importance. Antimicrobial/antiparasitic/antiviral therapy along with ERCP and interventional sonography/radiology provide effective treatment options.

Hepatobiliary and pancreatic ascariasis

Hepatobiliary and pancreatic ascariasis (HPA) was described as a clinical entity from Kashmir, India in 1985. HPA is caused by invasion and migration of nematode, Ascaris lumbricoides, in to the biliary tract and pancreatic duct. Patients present with biliary colic, cholangitis, cholecystitis, hepatic abscesses and acute pancreatitis. Ascarides traverse the ducts repeatedly, get trapped and die, leading to formation of hepatolithiasis. HPA is ubiquitous in endemic regions and in Kashmir, one such region, HPA is the etiological factor for 36.7%, 23%, 14.5% and 12.5% of all biliary diseases, acute pancreatitis, liver abscesses and biliary lithiasis respectively. Ultrasonography is an excellent diagnostic tool in visualizing worms in gut lumen and ductal system. The rational treatment for HPA is to give appropriate treatment for clinical syndromes along with effective anthelmintic therapy. Endotherapy in HPA is indicated if patients continue to have symptoms on medical therapy or when worms do not move out of ductal lumen by 3 wk or die within the ducts. The worms can be removed from the ductal system in most of the patients and such patients get regression of symptoms of hepatobiliary and pancreatic disease.

Human Ascariasis: Diagnostics Update

Soil-transmitted helminths (STHs) infect over one billion people worldwide. Ascariasis may mimic a number of conditions, and individual clinical diagnosis often requires a thorough work-up. Kato-Katz thick smears are the standard detection method for Ascaris and, despite low sensitivity, are often used for mapping and monitoring and evaluation of national control programmes. Although increased sampling (number of stools) and diagnostic (number of examinations per stool) efforts can improve sensitivity, Kato-Katz is less sensitive than other microscopy methods such as FLOTAC®. Antibody-based diagnostics may be a sensitive diagnostic tool; however, their usefulness is limited to assessing transmission in areas aiming for elimination. Molecular diagnostics are highly sensitive and specific, but high costs limit their use to individual diagnosis, drug - efficacy studies and identification of Ascaris suum. Increased investments in research on Ascaris and other STHs are urgently required for the development of diagnostic assays to support efforts to reduce human suffering caused by these infections.

Ascaris lumbricoides β carbonic anhydrase: a potential target enzyme for treatment of ascariasis

BACKGROUND

A parasitic roundworm, Ascaris lumbricoides, is the causative agent of ascariasis, with approximately 760 million cases around the world. Helminthic infections occur with a high prevalence mostly in tropical and developing xcountries. Therefore, design of affordable broad-spectrum anti-helminthic agents against a variety of pathogens, including not only A. lumbricoides but also hookworms and whipworms, is desirable. Beta carbonic anhydrases (β-CAs) are considered promising targets of novel anthelminthics because these enzymes are present in various parasites, while completely absent in vertebrates.

METHODS

In this study, we identified an A. lumbricoides β-CA (AIBCA) protein from protein sequence data using bioinformatics tools. We used computational biology resources and methods (including InterPro, CATH/Gene3D, KEGG, and METACYC) to analyze AlBCA and define potential roles of this enzyme in biological pathways. The AlBCA gene was cloned into pFastBac1, and recombinant AIBCA was produced in sf-9 insect cells. Kinetics of AlBCA were analyzed by a stopped-flow method.

RESULTS

Multiple sequence alignment revealed that AIBCA contains the two sequence motifs, CXDXR and HXXC, typical for β-CAs. Recombinant AIBCA showed significant CA catalytic activity with kcat of 6.0 × 10(5) s(-1) and kcat/KM of 4.3 × 10(7) M(-1) s(-1). The classical CA inhibitor, acetazolamide, showed an inhibition constant of 84.1 nM. Computational modeling suggests that the molecular architecture of AIBCA is highly similar to several other known β-CA structures. Functional predictions suggest that AIBCA might play a role in bicarbonate-mediated metabolic pathways, such as gluconeogenesis and removal of metabolically produced cyanate.

CONCLUSIONS

These results open new avenues to further investigate the precise functions of β-CAs in parasites and suggest that novel β-CA specific inhibitors should be developed and tested against helminthic diseases.

The role of endoscopy in the management of recurrent pyogenic cholangitis: a review

Recurrent pyogenic cholangitis (RPC) is a clinical syndrome characterized by repeated episodes of suppurative cholangitis due to hepatolithiasis and extrahepatic stones in the biliary ducts. It is now recognized as a distinct syndrome with a different natural history and pathoetiology than spontaneously occurring liver abscesses. Most commonly seen in East Asian populations, this syndrome is growing increasingly common in Western Nations due to migration patterns. The exact pathogenesis of RPC remains elusive; although colonization of the biliary tract with particular enteric bacterial species, in combination with possible dietary factors, has been attributed as causative factors. Hepatobiliary surgery, in particular segmental hepatectomy, is often described as the definitive treatment of choice for RPC. The exact role of endoscopic intervention has been less clearly described in the literature. This review focuses on the management of RPC while highlighting situations in which endoscopic retrograde cholangiopancreatography may be preferred over surgery as an initial or salvage therapeutic measure.

An unusual cause of pancreatitis in a 46-year-old returning traveller

A 46-year-old previously fit and well man, travelled to Jhelum, Pakistan for 6 weeks in early 2015. Four weeks after returning to the UK, he developed sudden onset epigastric pain, vomiting and fever. C reactive protein was 232 mg/L and amylase was 2061 U/L. He was treated conservatively as pancreatitis, with peripancreatic streaking and left colic gutter fluid on a CT abdominal scan. He was discharged and later attended the Hospital for Tropical Diseases, after coughing up an 8 cm male ascaris worm. He was treated for acute ascariasis infection, complicated by resolved mild-moderate pancreatitis, a common complication in the developing world but rarely seen among travellers.