Basidiobolomycosis: an unusual fungal infection mimicking inflammatory bowel disease

A case of basidiobolomycosis mimicking rhabdomyosarcoma: A diagnostic challenge

Basidiobolomycosis is a rare curable fungal infection caused by the saprophytic fungus Basidiobolus ranarum. It often causes skin infections but rarely infects visceral tissues in humans. Gastrointestinal basidiobolomycosis is an emerging form, which is rare but is increasingly reported. Due to its ability to mimic more common diagnoses such as chronic inflammatory disorders and malignancies, Basidiobolomycosis imposes a diagnostic challenge on most physicians. Therefore, a timely and correct diagnosis by laboratory tests and careful review of images along with proper medical management can save patients from invasive treatments and reduce both morbidity and mortality. Here, we present a rare case of an 8-year-old boy with basidiobolomycosis initially misdiagnosed as rhabdomyosarcoma. We aim to highlight basidiobolomycosis as a potential differential from masses on imaging under the right clinical circumstances and to provide radiologists with key imaging details to help recognize this infectious etiology and reduce its associated morbidity.

Basidiobolus haptosporus-like fungus as a causal agent of gastrointestinal basidiobolomycosis

Basidiobolus species were isolated from colonic biopsy samples of patients with gastrointestinal basidiobolomycosis (GIB) in southern Saudi Arabia. Isolated fungi were initially identified using classical mycological tools and confirmed by sequence analysis of the large subunit ribosomal RNA gene. Phenotypic tests revealed zygomycete-like fungi which conform to those of Basidiobolus species. Five sequenced strains formed a monophyletic clade in the 28S ribosomal RNA gene phylogenetic tree. They shared 99.97% similarity with B. haptosporus and 99.97% with B. haptosporus var. minor, and relatively lower similarity with B. ranarum (99.925%). The study suggests a new and a serious causal agent of GIB related to Basidiobolus haptosporus. These isolates are not related to B. ranarum, which is commonly linked to this disease.

Gastrointestinal basidiobolomycosis: Beware of the great masquerade a case report

Basidiobolomycosis is rare infection caused by the saprophytic fungus Basidiobolus ranarum. Gastrointestinal basidiobolomycosis is an infrequent, albeit, increasingly reported, emerging form of the disease and typically affects immunocompetent individuals with potentially grave sequelae if unrecognized. Acquaintance with this exceptionally rare fungus and its potential for presenting as gastrointestinal mass masquerading as colonic malignancy is critical for timely diagnosis, appropriate treatment and successful clinical outcome. We report a case of gastrointestinal basidiobolomycosis masquerading as colonic malignancy in a 29-year-old Omani patient successfully treated with combination of surgery and prolonged azole antifungal therapy.

Gastrointestinal basidiobolomycosis: An emerging mycosis difficult to diagnose but curable. Case report and review of the literature

BACKGROUND

Gastrointestinal basidiobolomycosis (GIB) is a rare mycosis affecting almost exclusively immunocompetent subjects.

METHODS

We describe a case of GIB caused by Basidiobolus ranarum in a 25-year-old Italian immunocompetent man resident in Ireland who presented a 2-month history of epigastric pain. Suspecting colon cancer he underwent a right hemicolectomy subsequently leading to a diagnosis of GIB by means of molecular biology. After surgery a 9-month therapy with itraconazole was employed with a good outcome. A review of medical literature regarding GIB cases published in the period 1964-2017 is presented.

RESULTS

One-hundred and two cases of GIB were included in this analysis. The disease was observed predominantly in male gender (74.5%) and children (41.2%). Abdominal pain was the single most common complaint (86.3%) followed by fever (40.2%) and evidence of an abdominal mass (30.4%). Peripheral blood eosinophilia was detected in 85.7% of cases. Most of the patients were diagnosed in Saudi Arabia (37.2%) followed by USA (21.6%) and Iran (20.6%). Surgery plus antifungal therapy was employed in the majority of patients (77.5%). An unfavourable outcome was documented globally in 18.6% of patients.

CONCLUSIONS

GIB seems to be an emerging intestinal mycosis among immunocompetent patients living in the Middle East and Arizona.

Paediatric case of gastrointestinal basidiobolomycosis mimicking appendicitis – Case report

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Basidiobolomycosis is a rare fungal infection that leads to subcutaneous infection.

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Gastrointestinal basidiobolomycosis is difficult to diagnose primarily due to its non-specific clinical presentation.

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Gastrointestinal basidiobolomycosis should be a differential especially in paediatric patients present with abdominal mass and eosinophilia.

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Optimal way to manage gastrointestinal basidiobolomycosis is by surgical resection followed by 3 months of antifungal treatment.

Introduction

Basidiobolomycosis is a rare fungal infection caused by Basidiobolus ranarum that normally leads to subcutaneous infection and, rarely, to involvement in the gastrointestinal tract.

Presentation of case

A 6-year-old boy presented to the Emergency department (ED) complaining of abdominal pain of a few weeks’ duration in the right lower quadrant, associated with fever and vomiting. A computed tomography (CT) of the abdomen was done. It showed an enlarged tubular structure in the right iliac fossa, a suspected appendicular lesion, and free fluid collection, as well as multiple enlarged mesenteric and right iliac lymph nodes. Based on these results, the decision was made to do surgical exploration on the patient. After two weeks, the patient developed tachycardia, abdominal distention, constipation, and spikes of fever. Two days later, re-exploration was performed. An ileostomy and colostomy were performed and drains inserted. Post-operative, the patient was pushed to paediatric intensive care unit (PICU), while still intubated and hemodynamically stable. However, he developed cardiac arrest on the same day and cardiopulmonary resuscitation (CPR) was performed, but he couldn't be resuscitated.

Discussion

The patient presented with severe abdominal pain in the right lower quadrant, as well as fever and vomiting. These complaints may have been misdiagnosed as appendicitis. The diagnosis of gastrointestinal basidiobolomycosis was confirmed by histopathology, based on a surgical specimen taken during the primary exploration. The management was a combination between surgical intervention and medical treatment.

An unusual case of gastrointestinal basidiobolomycosis mimicking colon cancer; literature and review

Gastrointestinal basidiobolomycosis (GIB), a rare fungal infection associated with high mortality, has been reported worldwide mainly from tropical and subtropical regions of Asia, USA, and Latin America. The clinical manifestations are highly diverse and non-specific depending on the underlying disease, but fever, abdominal pain, weight loss, diarrhea, constipation and chills have been observed. There are no prominent risk factors for GIB but climatic conditions and life style are related to this infection in arid and semi-arid regions. Therefore timely diagnosis and early treatment is a challenge. Herein, we present an unusual case of gastrointestinal basidiobolomycosis in a 54-year-old male, initially misdiagnosed as colon cancer. After follow-up, no evidence of relapse and the patient was successfully cured by liposomal amphotericin B. In addition, the differential diagnosis and histopathological findings are discussed with a review of the literature.

Disseminated angioinvasive basidiobolomycosis with a favourable outcome

Basidiobolomycosis, a rare fungal infection, is of worldwide distribution but areas commonly involved include the tropical areas of Africa, USA and South East Asia. 88% of the cases are reported among patients younger than 20 years. Many of the case reports in Saudi Arabia are from Tohama area where our patient lives. The diagnosis tends to be overlooked as the presentation may mimic colonic carcinoma in adults or inflammatory bowel diseases and tuberculosis in both children and adults. Angioinvasion seen in our patient is extremely rare suggesting the diagnosis of mucormycosis and resulting in a delay in choosing the most appropriate treatment. We report this case to remind physicians and surgeons to consider this diagnosis in patients from endemic area presenting with such conditions.

Human Pathogenic Entomophthorales

The pathogenic entomophthoralean fungi cause infection in insects and mammalian hosts. Basidiobolus and Conidiobolus species can be found in soil and insect, reptile, and amphibian droppings in tropical and subtropical areas. The life cycles of these fungi occur in these environments where infecting sticky conidia are developed. The infection is acquired by insect bite or contact with contaminated environments through open skin. Conidiobolus coronatus typically causes chronic rhinofacial disease in immunocompetent hosts, whereas some Conidiobolus species can be found in immunocompromised patients. Basidiobolus ranarum infection is restricted to subcutaneous tissues but may be involved in intestinal and disseminated infections. Its early diagnosis remains challenging due to clinical similarities to other intestinal diseases. Infected tissues characteristically display eosinophilic granulomas with the Splendore-Höeppli phenomenon. However, in immunocompromised patients, the above-mentioned inflammatory reaction is absent. Laboratory diagnosis includes wet mount, culture serological assays, and molecular methodologies. The management of entomophthoralean fungi relies on traditional antifungal therapies, such as potassium iodide (KI), amphotericin B, itraconazole, and ketoconazole, and surgery. These species are intrinsically resistant to some antifungals, prompting physicians to experiment with combinations of therapies. Research is needed to investigate the immunology of entomophthoralean fungi in infected hosts. The absence of an animal model and lack of funding severely limit research on these fungi.

Basidiobolomycosis in Togo: clinico-pathological study of a series of 12 presumed cases

OBJECTIVE

The purpose of our study was to describe the histological diagnosed of the Basidiobolomycosis cases from 1990 to 2017 (28 years) in the only Pathology Anatomy Laboratory in Togo.

RESULTS

A total of 12 cases of suspected Basidiobolomycosis have been identified. The sex ratio (M/F) was 2. The average age of the patients was 24.8 ± 1.6 years. Six patients (6/12) had a pathological history: HIV infection (n = 4 cases) and tuberculosis (n = 2 cases). The clinical manifestations were localized to pure skin (n = 9 cases), skin and mucous digestive (n = 2 cases) and disseminated (n = 1 cases). Direct mycological examination and culture in 4 patients was positive in 3 patients. The samples examined consisted of 11 cutaneous biopsies measuring 1-3 cm and a biopsy of the intestinal mucosa. Histology showed granulomatous inflammation of the dermohypodermal site with numerous giant cells associated with eosinophilic polynuclear cells, in which there are 5-7 mm non-septate, irregular mycelial filaments. Patients were treated with ketoconazole at a dose of 10 mg/kg daily. The progression of the patients' condition was favorable after 4 weeks of treatment with a regression of the closets size. Patients were completely healed after 8 weeks of treatment, without recurrence after 6 months. No deaths have been recorded.

Subcutaneous Granulomatous Inflammation due to Basidiobolomycosis: Case Reports of 3 Patients in Buruli Ulcer Endemic Areas in Benin

BACKGROUND

Basidiobolomycosis is a rare subcutaneous mycosis, which can be mistaken for several other diseases, such as soft tissue tumors, lymphoma, or Buruli ulcer in the preulcerative stage. Microbiological confirmation by PCR for Basidiobolus ranarum and culture yield the most specific diagnosis, yet they are not widely available in endemic areas and with varying sensitivity. A combination of histopathological findings, namely, granulomatous inflammation with giant cells, septate hyphal fragments, and the Splendore-Hoeppli phenomenon, can confirm basidiobolomycosis in patients presenting with painless, hard induration of soft tissue.

CASE PRESENTATIONS

We report on three patients misdiagnosed as suffering from Buruli ulcer, who did not respond to Buruli treatment. Histopathological review of the tissue sections from these patients suggests basidiobolomycosis. All patients had been lost to follow-up, and none received antifungal therapy. On visiting the patients at their homes, two were reported to have died of unknown causes. The third patient was found alive and well and had experienced local spontaneous healing.

CONCLUSION

Basidiobolomycosis is a rare subcutaneous fungal disease mimicking preulcerative Buruli ulcer. We stress the importance of the early recognition by clinicians and pathologists of this treatable disease, so patients can timely receive antifungal therapy.

Fungal inflammatory masses masquerading as colorectal cancer: a case report

Background

Non malignant invasive tumors of the colon and rectum are very rare. Gastrointestinal Basidiobolomycosis can present as a mass lesion mimicking colorectal cancer.

Case presentation

A 56 year old Caucasian male was evaluated for abdominal and pelvic pain for 4 weeks complicated by acute urinary retention. Radiological evaluation showed him to have recto-sigmoid and cecal mass. Endoscopic examination and biopsies did not reveal a definite diagnosis. Computerized tomography guided biopsy of the mass showed fungal elements consistent with gastrointestinal basidiobolomycosis. He was treated with Itraconazole for 12 months with very good clinical and radiological response.

Conclusion

Basidiobolomycosis of the gastrointestinal tract should be considered during evaluation of colorectal masses with atypical presentation. It is a rare entity seen more in endemic regions of the world for basidiobolomycosis including southwestern United States.

Gastrointestinal basidiobolomycosis with hepatic dissemination: a case report

INTRODUCTION

Gastrointestinal basidiobolomycosis (GIB) is an emerging fungal infection with a few cases reported worldwide. It is caused by Basidiobolus ranarum, which does not usually invade blood vessels and rarely disseminates.

CASE PRESENTATION

We present a rare case of GIB with hepatic dissemination in a 12-year-old Yemeni boy living in southwestern Saudi Arabia. The initial provisional diagnosis was intestinal lymphoma, and a right hemicolectomy was carried out, but histopathological assessment ruled out lymphoma and suggested intestinal tuberculosis. Two weeks after starting antituberculous medications, the patient was referred to our hospital because of fever and right upper abdominal discomfort. There was leukocytosis with marked eosinophilia, and a liver biopsy showed evidence of B. ranarum infection. A second opinion by histopathological examination of resected tissues diagnosed colonic basidiobolomycosis. The patient was treated successfully with itraconazole.

CONCLUSION

GIB is an emerging disease in southwestern Saudi Arabia and should be considered in a patient with an abdominal mass and eosinophilia coming from this region. Persistent elevation of leukocytes and eosinophils after surgical resection of the affected tissue could be used as a predictor of fungal dissemination. Further research is needed for a better understanding of GIB.

Human Fungal Pathogens of Mucorales and Entomophthorales

In recent years, we have seen an increase in the number of immunocompromised cohorts as a result of infections and/or medical conditions, which has resulted in an increased incidence of fungal infections. Although rare, the incidence of infections caused by fungi belonging to basal fungal lineages is also continuously increasing. Basal fungal lineages diverged at an early point during the evolution of the fungal lineage, in which, in a simplified four-phylum fungal kingdom, Zygomycota and Chytridiomycota belong to the basal fungi, distinguishing them from Ascomycota and Basidiomycota. Currently there are no known human infections caused by fungi in Chytridiomycota; only Zygomycotan fungi are known to infect humans. Hence, infections caused by zygomycetes have been called zygomycosis, and the term "zygomycosis" is often used as a synonym for "mucormycosis." In the four-phylum fungal kingdom system, Zygomycota is classified mainly based on morphology, including the ability to form coenocytic (aseptated) hyphae and zygospores (sexual spores). In the Zygomycota, there are 10 known orders, two of which, the Mucorales and Entomophthorales, contain species that can infect humans, and the infection has historically been known as zygomycosis. However, recent multilocus sequence typing analyses (the fungal tree of life [AFTOL] project) revealed that the Zygomycota forms not a monophyletic clade but instead a polyphyletic clade, whereas Ascomycota and Basidiomycota are monophyletic. Thus, the term "zygomycosis" needed to be further specified, resulting in the terms "mucormycosis" and "entomophthoramycosis." This review covers these two different types of fungal infections.

Gastrointestinal Basidiobolomycosis: First case report from Oman and literature review

Gastrointestinal basidiobolomycosis (GIB) is a rare fungal infection with few reported cases worldwide. We report here the first case diagnosed in Oman in a previously healthy 5-year-old Omani female child who had been thought initially to have an abdominal malignancy. The case was referred to the Royal Hospital, Muscat, Oman, in July 2012. She was treated successfully with surgical resection and prolonged antifungal therapy (voriconazole). Physicians, including clinicians, radiologists and pathologists, should have a high index of suspicion for GIB when a patient presents with an abdominal mass and fever.

Gastrointestinal basidiobolomycosis: mimicking Crohns disease case report and review of the literature

Gastrointestinal basidiobolomycosis (GIB) is an unusual fungal infection that manifests in the skin and rarely involves other systems. All of the few cases of GIB reported so far were diagnosed with difficulty, necessitating laparotomy and resection of the inflamed part of the bowel. We report a child with GIB who was successfully diagnosed endoscopically without surgical intervention.

Gastrointestinal basidiobolomycosis treated with posaconazole

A 67 year-old Caucasian male from Arizona presented with indolent symptoms of intestinal obstruction and hydronephrosis, found at surgery to be caused by a mass involving the terminal ileum and cecum, extending into the posterior abdominal wall and obstructing the right ureter. Histopathology was diagnostic of basidiobolomycosis. PCR of tissue and sequencing identified the fungus as, Basidiobolus ranarum. During one year of posaconazole treatment, the residual mass shrank, hydronephrosis was relieved and peripheral eosinophilia resolved.

Surgical management of gastrointestinal basidiobolomycosis in pediatric patients

INTRODUCTION

Gastrointestinal basidiobolomycosis (GIB) is a rare fungal disease. We reviewed our experience with this disease over the last 10 years, with special emphasis on the surgical aspects.

METHODS

A retrospective chart review was conducted for pediatric patients with GIB who were managed at our institution over the last 10 years. Demographic, clinical, and follow-up data were collected, and descriptive data were generated.

RESULTS

Nine patients with a median age of 7 years were managed for GIB over the study period. Six patients were managed surgically. Four had colonic and liver involvement, 1 had a left hepatic lesion, and 1 had a porta hepatic mass. One patient had multiple liver lesions and was managed medically, and 2 patients had disseminated disease and died shortly after presentation. Tissue biopsies confirmed the diagnosis, and all received antifungal treatment. Patients were followed up for a median of 6 years. All live patients are free of disease, and 4 are still on antifungal medications.

CONCLUSIONS

Gastrointestinal basidiobolomycosis is an aggressive disease that requires early surgical intervention to avoid complications and hasten disease eradication. Long-term follow-up is warranted, given the significant potential for complications.

Gastrointestinal basidiobolomycosis in a child; an unusual fungal infection mimicking fistulising Crohn's disease

BACKGROUND

Gastrointestinal basidiobolomycosis is a rare disease caused by the fungus Basidiobolus ranarum. It has been reported in both children and adults. The disease mainly affects the colon and the small bowel; however, cases of the stomach, liver, pancreas, and renal system being affected have been reported.

CASE REPORT

A 2 year old boy presented with the following symptoms; abdominal pain, vomiting, diarrhea, fever and palpable right iliac fossa mass. Laboratory investigations revealed elevated inflammatory markers and peripheral eosinophilia. Colonoscopy showed severely inflamed mucosa of the terminal ileum, cecum and ascending colon. CT scan of the abdomen demonstrated an inflammatory mass with wall thickening of the terminal ileum and the colon. Surgical exploration demonstrated retroperitoneal mass and inflamed terminal ileum, cecum and ascending colon. Upon laparotomy, multiple internal fistulas involving the bowel loops, the urinary bladder, the right ureter and the gallbladder were observed. Further investigations using histopathology of the resected diseased bowel showed extensive necrosis, multinucleated giant cells and numerous eosinophils and large fungal hyphae surrounded by strongly eosinophilic material were seen in the tissue suggestive of B. ranarum infection. The patient responded well to treatment with voriconazole.

CONCLUSION

Gastrointestinal basidiobolomycosis should be considered in the differential diagnosis of every child presenting with abdominal pain, fever and palpable abdominal mass with peripheral eosinophilia. The presence of bowel inflammation and fistulas should not preclude such diagnosis.

Emergence of gastrointestinal basidiobolomycosis in the United States, with a review of worldwide cases

BACKGROUND

We examined the epidemiology, clinical manifestations, histopathology, management, and outcomes of gastrointestinal basidiobolomycosis, an uncommon manifestation of infection caused by the fungus Basidiobolus ranarum.

METHODS

In this retrospective observational cohort study, cases of gastrointestinal basidiobolomycosis in the United States were identified by reviewing medical records from Mayo Clinic Hospital (Phoenix, AZ) and contacting local infectious diseases specialists, pathologists, gastroenterologists, the Arizona Department of Health Services, health departments of adjacent states, the Armed Forces Institute of Pathology, and the US Centers for Disease Control and Prevention. A comprehensive literature review identified additional cases worldwide.

RESULTS

Of 44 patients (mean age, 37 years [range, 2-81 years]) with gastrointestinal basidiobolomycosis, most were from the United States (19 patients [43%], of whom 17 [89%] were from Arizona) or Saudi Arabia (11 [25%]). Most (28 [64%]) were previously healthy. Common chronic medical conditions among 15 patients (34%) were diabetes mellitus (8 patients [18%]) and gastric disorders (7 [16%]). Common findings were abdominal pain (37 patients [84%]) and a palpable abdominal mass (19 [43%]). Intraabdominal malignancy was the leading provisional diagnosis (19 patients [43%]). The large bowel was involved in 36 (82%), the small intestine in 16 (36%), and the liver or gallbladder in 13 (30%). Characteristic histopathologic findings were observed in 43 (98%). Eight patients (18%) died. Combined surgical intervention and antifungal therapy was the preferred treatment.

CONCLUSIONS

Gastrointestinal basidiobolomycosis is an emerging invasive fungal infection in desert regions of the US Southwest. Clinical findings mimic malignancy and inflammatory bowel disease. Surgical excision and prolonged antifungal therapy are associated with favorable outcomes.

Development of a specific polymerase chain reaction assay for the detection of Basidiobolus

The etiology of chronic diarrhea is complex in humans and animals. It is always necessary to evaluate a list of differential diagnosis, including bacteria, protozoa and fungi. Basidiobolomycosis is a fungal disease reported sporadically worldwide, mainly caused by B. ranarum, a frequent organism found in soil or in the intestine and skin of lizards and frogs. It is an opportunistic pathogen that causes infections characterized by granulomatous lesions in the subcutaneous tissues as well as in the intestinal wall in humans and animals. In this work we have developed a PCR technique to differentiate Basidiobolus from other causes of intestinal disease in dogs and humans. To test the specificity of the PCR assay we included closely related organisms, common intestinal microbiota and pathogenic organisms, such as Aspergillus, Candida, Cryptosporidium, Escherichia, Giardia, Mucor, Proteus, Rhizopus and Salmonella. Pythium insidiosum, which cause clinically similar disease in dogs but require a different treatment. Only Basidiobolus was positive to the PCR assay.

Basidiobolomycosis of the colon masquerading as stenotic colon cancer

Basidiobolus ranarum is a widespread saprophyte fungus with pathogenic potential. It affects mainly the subcutaneous tissues of the trunk and limbs. Relatively recently, occasional reports of gastrointestinal basidiobolomycosis appeared in the literature. Due to the rarity of the condition and the nonspecific presenting features, the correct diagnosis is usually hard to reach. In this paper, we describe the clinical course of an otherwise healthy female, who presented with a colonic mass. She received subtotal colectomy followed by oral itraconazole, with successful outcome.

Basidiobolomycosis of the nose and face: a case report and a mini-review of unusual cases of basidiobolomycosis

BACKGROUND

Subcutaneous zygomycosis is a chronic infection caused by fungus of the order Entomophthorales. It can have varying presentations and presents in the nose and face area with gradually progressing subcutaneous swelling that may be difficult to diagnose unless a strong suspicion of fungal involvement is maintained. We present a case of subcutaneous zygomycosis in a 35-year-old male patient, resident of a North Indian state. The patient was diagnosed to be suffering from subcutaneous zygomycosis, the causative agent being Basidiobolus ranarum identified on culture and lactophenol cotton blue mount preparation. He responded well to treatment with Itraconazole and Terbinafine and is asymptomatic on follow-up.

CONCLUSIONS

Involvement of the nose and subcutaneous tissues of the face in Basidiobolomycosis is rare. The infection is more common in children, but the case presented here is an adult. Its occurrence in a native of North India is also uncommon. Previous studies have mostly reported good response to potassium iodide therapy. Our patient responded well to Itraconazole. The presentation can be a diagnostic dilemma if fungal smear and culture is not sought, so this rare entity should be kept in mind in cases of indolent infections of the nose and facial soft tissues.

Gastrointestinal basidiobolomycosis: an unusual fungal infection mimicking colon cancer

CONTEXT

-Basidiobolomycosis is a rare disease caused by the fungus Basidiobolus ranarum, an environmental saprophyte found worldwide. Patients with B ranarum infection may present with subcutaneous, gastrointestinal, or systemic lesions. Gastrointestinal basidiobolomycosis poses diagnostic difficulties, as its clinical presentation is nonspecific, with no identifiable risk factors.

OBJECTIVE

-To discuss and compare the clinical features and histopathologic findings and other ancillary techniques that could be helpful in identifying gastrointestinal basidiobolomycosis.

DESIGN

-We report 3 cases of gastrointestinal basidiobolomycosis and describe the clinical and morphologic findings while emphasizing the importance of identifying this unusual entity on endoscopic biopsies, thus avoiding unnecessary major surgeries. Fungal cultures were also performed, which are of diagnostic significance. Our first patient was lost to follow-up; however, patients 2 and 3 were followed up for 4 and 2 years, respectively.

RESULTS

-In all 3 cases, patients presented with a clinical profile suggestive of malignancy. None of the patients gave any specific history. There was widespread abdominal disease with peritoneal involvement and colonic masses. Colonoscopic biopsy specimens showed nonspecific inflammation in 1 case; however, they showed only granulomatous inflammation in a second case and granulomas associated with fungal hyphae in a third. Typical morphology included hyphae, irregularly branched, thin-walled, occasionally septated and surrounded by a thick eosinophilic cuff (Splendore-Hoeppli phenomenon).

CONCLUSION

-Gastrointestinal basidiobolomycosis can be detected on small endoscopic biopsy. The unequivocal diagnosis requires microbiologic cultivation of the fungus obtained from tissues. The prognosis for this disease is usually favorable as seen in 3 of our cases; however, cases with fatal outcome are on record.

Histological and ultrastructural features of gastrointestinal basidiobolomycosis

Basidiobolus ranarum is a fungus found in the dung of amphibians, reptiles, and insectivorous bats. Its structural elements include both hyphae and zygospores. Patients with B. ranarum infection may present with subcutaneous, gastrointestinal, or systemic lesions. Here we report a case of gastrointesinal badidiomycosis in a 13-year-old male child who presented with acute abdomen. Exploration revealed a mass in the ascending colon. On histology, transmural granulomatous inflammation composed of abundant eosinophils, lymphocytes, histiocytes and giant cells was seen. Histochemical stains revealed broad, non-septate, hyphae-like structures surrounded by an eosinophilic sheath. On an ultrastructural level, fungal hyphae, spores, and macrophage-laden crystalloids were observed. The diagnosis of gastrointestinal basidiobolomycosis was established and the patient received antifungal treatment. This paper reviews the relevant literature regarding basidiomycosis, and discusses its diverse clinicopathological features, as well as distinguishing it from other diseases.

Zygomycosis: the re-emerging fungal infection

Invasive fungal infections are major medical complications in immunocompromised patients. The recent rise in the incidence of cancer and the increased use of newer medical treatment modalities, including organ transplantations, have resulted in growing numbers of highly immunosuppressed individuals. Although aspergillosis and candidiasis are among the most common invasive mycoses in such patients, there is evidence that the incidence of infectious diseases caused by Zygomycetes has risen significantly over the past decade. Patients with diabetes, malignancies, solid organ or bone marrow transplants, or iron overload and those receiving immunosuppressive agents, deferoxamine therapy, or broad-spectrum antimicrobial drugs are at highest risk for zygomycosis. This review details the emergence and importance of zygomycosis in current clinical practice and its manifestations and management. The etiologic species, pathogenesis and risk factors for zygomycosis are reviewed and updated. The clinical spectrum of zygomycosis is now broader, and it can be difficult to distinguish between mucormycosis and enthomophthoramycosis, both of which can manifest as disease ranging from a superficial infection to an angioinvasive infection with high mortality. Finally, the three-part treatment strategy (antifungal drugs, surgery, control of underlying diseases) is reviewed. Lipid formulations of amphotericin B are the antifungal agents of choice for treatment of zygomycosis. A novel antifungal triazole, posaconazole, has been developed and may become approved for treatment of zygomycosis. The clinical experience with adjunctive treatments like colony-stimulating factors, interferon-gamma, and hyperbaric oxygen therapy is still limited.

Use of the laparoscopic-endoscopic approach, the so-called "rendezvous" technique, in cholecystocholedocholithiasis: a valid method in cases with patient-related risk factors for post-ERCP pancreatitis

BACKGROUND

Several studies have shown the efficacy and effectiveness of the combined endoscopic-laparoscopic "rendezvous" technique for treatment of gallbladder and bile duct stones without complications, particularly pancreatitis. The so-called rendezvous technique consists of laparoscopic cholecystectomy standards with intraoperative cholangiography followed by endoscopic sphincterotomy (EST). The sphincterotome is driven across the papilla through a guidewire inserted by the transcystic route. This method allows easier and faster cannulation, thus avoiding papillary edema and pancreatic trauma. The aim of this study was to evaluate whether this method is effective in eliminating ductal stones and to verify whether the risk of postprocedure pancreatitis is diminished.

METHODS

From January 2002 to September 2004, we enrolled 256 patients with cholecystocholedolithiasis detected by transabdominal ultrasound and magnetic resonance cholangiopancreatography. One hundred and twenty of these had one or more patient-related risk factors for post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis, so they were randomized into two groups of 60 patients. In group A, the patients were treated in a single step with videolaparoscopic cholecystectomy, intraoperative cholangiography, and EST during the surgical procedure with the rendezvous technique. In group B, preoperative ERCP and EST were performed by using a traditional method of bile duct cannulation.

RESULTS

No cases of post-ERCP pancreatitis were observed in group A, whereas six cases of acute post-ERCP pancreatitis occurred in group B (five mild and one moderate) (p = 0.0274). No procedure-related mortality was recorded.

CONCLUSION

In cholecysthocholedocholithiasis, the combined laparoscopic-endoscopic approach prevents post-ERCP pancreatitis in cases with patient-related risk factors for this complication.

Emerging fungal diseases: the importance of the host

More yeasts and molds are now recognized to cause more human disease than ever before. This development is not due to a change in the virulence of these fungi, but rather to changes in the human host. These changes include immunosuppression secondary to the pandemic of HIV, the use of life-saving advances in chemotherapy and organ transplantation, and the use of corticosteroids and other immunosuppressive agents to treat a variety of diseases. Fungi that were once considered common saprophytes are now recognized as potential pathogens in these patients. This situation necessitates better communication than ever between the clinician, pathologist, and clinical mycologist to ensure the prompt and accurate determination of the cause of fungal diseases.

Disseminated basidiobolomycosis in an immunocompetent woman

Basidiobolomycosis is a chronic subcutaneous infection of the trunk and limbs due to Basidiobolus ranarum. The disease is well known in tropical areas, although recent cases of gastrointestinal basidiobolomycosis have also been reported in Arizona. We describe a young immunocompetent women who had presented with eosinophilia and lung infiltrates. She subsequently died, and diagnosis of disseminated basidiobolomycosis was made on the basis of histological features at autopsy.

Antimicrobial peptide defenses against pathogens associated with global amphibian declines

Global declines of amphibian populations are a source of great concern. Several pathogens that can infect the skin have been implicated in the declines. The pathogen most frequently associated with recent die-offs is a chytrid fungus, Batrachochytrium dendrobatidis. A second fungus, Basidiobolus ranarum, was isolated from declining populations of Wyoming toads. A third pathogen, Aeromonas hydrophila, is an opportunistic bacterium found in healthy frogs, but capable of inducing disease. Among the immune defense mechanisms used by amphibians is the production of antimicrobial peptides in granular glands in the skin. These packets of natural antibiotics can be emptied onto the skin when the amphibian is injured. To determine whether antimicrobial skin peptides defend against these amphibian pathogens, six peptides (magainin I, magainin II, PGLa, CPF, ranalexin, and dermaseptin), from three species, and representing three structurally different families of peptides, were tested in growth inhibition assays. We show here that the peptides can kill or inhibit growth of both fungi but not Aeromonas. Although each peptide varied in its effectiveness, at least one from each species was effective against both fungi at a concentration of about 10-20 microM. This is the first direct evidence that antimicrobial peptides in the skin can operate as a first line of defense against the organisms associated with global amphibian declines. It suggests that this innate defense mechanism may play a role in preventing or limiting infection by these organisms.

Basidiobolus ranarum as an etiologic agent of gastrointestinal zygomycosis

Basidiobolus ranarum is a known cause of subcutaneous zygomycosis. Recently, its etiologic role in gastrointestinal infections has been increasingly recognized. While the clinical presentation of the subcutaneous disease is quite characteristic and the disease is easy to diagnose, gastrointestinal basidiobolomycosis poses diagnostic difficulties; its clinical presentation is nonspecific, there are no identifiable risk factors, and all age groups are susceptible. The case of gastrointestinal basidiobolomycosis described in the present report occurred in a 41-year-old Indian male who had a history of repair of a left inguinal hernia 2 years earlier and who is native to the southern part of India, where the subcutaneous form of the disease is indigenous. Diagnosis is based on the isolation of B. ranarum from cultures of urine and demonstration of broad, sparsely septate hyphal elements in histopathologic sections of the colon, with characteristic eosinophilic infiltration and the Splendore-Hoeppli phenomenon. The titers of both immunoglobulin G (IgG) and IgM antibodies to locally produced antigen of the fungus were elevated. The patient failed to respond to 8 weeks of amphotericin B therapy, and the isolate was later found to be resistant to amphotericin B, itraconazole, fluconazole, and flucytosine but susceptible to ketoconazole and miconazole. One other noteworthy feature of the fungus was that the patient's serum showed raised levels of Th2-type cytokines (interleukins 4 and 10) and tumor necrosis factor alpha. The present report underscores the need to consider gastrointestinal basidiobolomycosis in the differential diagnosis of inflammatory bowel diseases and suggests that, perhaps, more time should be invested in developing standardized serologic reagents that can be used as part of a less invasive means of diagnosis of the disease.

Indications and efficacy of botulinum toxin in disorders of the gastrointestinal tract

In recent years, botulinum toxin type A (BT) has been found to be effective in the treatment of various spastic disorders of smooth muscle in the upper and lower gastrointestinal tract. The short-term efficacy of intrasphincteric injection of BT in achalasia is now well established, however, because of the chronic nature of the disease, patients will require repeated injections at regular intervals. In contrast, after a single injection into the anal sphincter, BT has impressively high healing rate with minimal side effects. BT remains a novel therapeutic approach in a range of other gastrointestinal motility disorders including diffuse oesophageal spasm, sphincter of Oddi dysfunction and anismus, and the list of its indications is increasing. BT seems to be safe but as its long-term effects remain unestablished, it should be used with caution in younger patients. In this review we discuss the mechanism of action, indications, efficacy and side-effects of BT with its use in various areas of gastrointestinal tract.

Zygomycetes in human disease

The Zygomycetes represent relatively uncommon isolates in the clinical laboratory, reflecting either environmental contaminants or, less commonly, a clinical disease called zygomycosis. There are two orders of Zygomycetes containing organisms that cause human disease, the Mucorales and the Entomophthorales. The majority of human illness is caused by the Mucorales. While disease is most commonly linked to Rhizopus spp., other organisms are also associated with human infection, including Mucor, Rhizomucor, Absidia, Apophysomyces, Saksenaea, Cunninghamella, Cokeromyces, and Syncephalastrum spp. Although Mortierella spp. do cause disease in animals, there is no longer sufficient evidence to suggest that they are true human pathogens. The spores from these molds are transmitted by inhalation, via a variety of percutaneous routes, or by ingestion of spores. Human zygomycosis caused by the Mucorales generally occurs in immunocompromised hosts as opportunistic infections. Host risk factors include diabetes mellitus, neutropenia, sustained immunosuppressive therapy, chronic prednisone use, iron chelation therapy, broad-spectrum antibiotic use, severe malnutrition, and primary breakdown in the integrity of the cutaneous barrier such as trauma, surgical wounds, needle sticks, or burns. Zygomycosis occurs only rarely in immunocompetent hosts. The disease manifestations reflect the mode of transmission, with rhinocerebral and pulmonary diseases being the most common manifestations. Cutaneous, gastrointestinal, and allergic diseases are also seen. The Mucorales are associated with angioinvasive disease, often leading to thrombosis, infarction of involved tissues, and tissue destruction mediated by a number of fungal proteases, lipases, and mycotoxins. If the diagnosis is not made early, dissemination often occurs. Therapy, if it is to be effective, must be started early and requires combinations of antifungal drugs, surgical intervention, and reversal of the underlying risk factors. The Entomophthorales are closely related to the Mucorales on the basis of sexual growth by production of zygospores and by the production of coenocytic hyphae. Despite these similarities, the Entomophthorales and Mucorales have dramatically different gross morphologies, asexual reproductive characteristics, and disease manifestations. In comparison to the floccose aerial mycelium of the Mucorales, the Entomophthorales produce a compact, glabrous mycelium. The asexually produced spores of the Entomophthorales may be passively released or actively expelled into the environment. Human disease with these organisms occurs predominantly in tropical regions, with transmission occurring by implantation of spores via minor trauma such as insect bites or by inhalation of spores into the sinuses. Conidiobolus typically infects mucocutaneous sites to produce sinusitis disease, while Basidiobolus infections occur as subcutaneous mycosis of the trunk and extremities. The Entomophthorales are true pathogens, infecting primarily immunocompetent hosts. They generally do not invade blood vessels and rarely disseminate. Occasional cases of disseminated and angioinvasive disease have recently been described, primarily in immunocompromised patients, suggesting a possible emerging role for this organism as an opportunist.

Zygomycetes in human disease

The Zygomycetes represent relatively uncommon isolates in the clinical laboratory, reflecting either environmental contaminants or, less commonly, a clinical disease called zygomycosis. There are two orders of Zygomycetes containing organisms that cause human disease, the Mucorales and the Entomophthorales. The majority of human illness is caused by the Mucorales. While disease is most commonly linked to Rhizopus spp., other organisms are also associated with human infection, including Mucor, Rhizomucor, Absidia, Apophysomyces, Saksenaea, Cunninghamella, Cokeromyces, and Syncephalastrum spp. Although Mortierella spp. do cause disease in animals, there is no longer sufficient evidence to suggest that they are true human pathogens. The spores from these molds are transmitted by inhalation, via a variety of percutaneous routes, or by ingestion of spores. Human zygomycosis caused by the Mucorales generally occurs in immunocompromised hosts as opportunistic infections. Host risk factors include diabetes mellitus, neutropenia, sustained immunosuppressive therapy, chronic prednisone use, iron chelation therapy, broad-spectrum antibiotic use, severe malnutrition, and primary breakdown in the integrity of the cutaneous barrier such as trauma, surgical wounds, needle sticks, or burns. Zygomycosis occurs only rarely in immunocompetent hosts. The disease manifestations reflect the mode of transmission, with rhinocerebral and pulmonary diseases being the most common manifestations. Cutaneous, gastrointestinal, and allergic diseases are also seen. The Mucorales are associated with angioinvasive disease, often leading to thrombosis, infarction of involved tissues, and tissue destruction mediated by a number of fungal proteases, lipases, and mycotoxins. If the diagnosis is not made early, dissemination often occurs. Therapy, if it is to be effective, must be started early and requires combinations of antifungal drugs, surgical intervention, and reversal of the underlying risk factors. The Entomophthorales are closely related to the Mucorales on the basis of sexual growth by production of zygospores and by the production of coenocytic hyphae. Despite these similarities, the Entomophthorales and Mucorales have dramatically different gross morphologies, asexual reproductive characteristics, and disease manifestations. In comparison to the floccose aerial mycelium of the Mucorales, the Entomophthorales produce a compact, glabrous mycelium. The asexually produced spores of the Entomophthorales may be passively released or actively expelled into the environment. Human disease with these organisms occurs predominantly in tropical regions, with transmission occurring by implantation of spores via minor trauma such as insect bites or by inhalation of spores into the sinuses. Conidiobolus typically infects mucocutaneous sites to produce sinusitis disease, while Basidiobolus infections occur as subcutaneous mycosis of the trunk and extremities. The Entomophthorales are true pathogens, infecting primarily immunocompetent hosts. They generally do not invade blood vessels and rarely disseminate. Occasional cases of disseminated and angioinvasive disease have recently been described, primarily in immunocompromised patients, suggesting a possible emerging role for this organism as an opportunist.

Phylogeny and PCR identification of clinically important Zygomycetes based on nuclear ribosomal-DNA sequence data

A molecular database for all clinically important Zygomycetes was constructed from nucleotide sequences from the nuclear small-subunit (18S) ribosomal DNA and domains D1 and D2 of the nuclear large-subunit (28S) ribosomal DNA. Parsimony analysis of the aligned 18S and 28S DNA sequences was used to investigate phylogenetic relationships among 42 isolates representing species of Zygomycetes reported to cause infections in humans and other animals, together with commonly cultured contaminants, with emphasis on members of the Mucorales. The molecular phylogeny provided strong support for the monophyly of the Mucorales, exclusive of Echinosporangium transversale and Mortierella spp., which are currently misclassified within the Mucorales. Micromucor ramannianus, traditionally classified within Mortierella, and Syncephalastrum racemosum represent the basal divergences within the Mucorales. Based on the 18S gene tree topology, Absidia corymbifera and Rhizomucor variabilis appear to be misplaced taxonomically. A. corymbifera is strongly supported as a sister group of the Rhizomucor miehei-Rhizomucor pusillus clade, while R. variabilis is nested within Mucor. The aligned 28S sequences were used to design 13 taxon-specific PCR primer pairs for those taxa most commonly implicated in infections. All of the primers specifically amplified DNA of the size predicted based on the DNA sequence data from the target taxa; however, they did not cross-react with phylogenetically related species. These primers have the potential to be used in a PCR assay for the rapid and accurate identification of the etiological agents of mucormycoses and entomophthoromycoses.

A review of zygomycosis due to Basidiobolus ranarum

Zygomycosis due to Basidiobolus ranarum (entomophthoromycosis basidiobolae, subcutaneous zygomycosis, subcutaneous phycomycosis, basidiobolomycosis) is a granulomatous infection of the skin and subcutaneous tissues characterized by the formation of fluctuant firm and non-tender swellings, generally on the extremities, trunk and rarely other parts of the body. The causative agent is common in soil, decaying vegetable matter, and the gastrointestinal tracts of amphibians, reptiles, fish and bats. It is presumed that infection is acquired through exposure to B. ranarum following minor trauma to skin or insect bites. The disease usually occurs in children, less often in adolescents and rarely in adults. Males are much more frequently affected than females. Laboratory diagnosis is based on histopathology and culture. The typical histopathological feature is the presence of thin-walled, broad often aseptate hyphae or hyphal fragments with an eosinophilic sheath, frequently phagocytized within giant cells. Basidiobolus ranarum is known to produce several enzymes, e.g. lipase and protease that probably play roles in the pathogenesis of infections caused by this mould. An immunological test has been developed for specific diagnosis of the disease. Though potassium iodide (KI) has been the traditional drug employed in the treatment of infections by B. ranarum, several other drugs, viz amphotericin B, cotrimoxazole, ketoconazole, itraconazole and fluconazole have been successfully tried.

Low-dose midazolam sedation: an option for patients undergoing serial hepatic venous pressure measurements

The hepatic venous pressure gradient (HVPG) is becoming increasingly used clinically. It is useful in the differential diagnosis of portal hypertension and provides a prognostic index in cirrhotic patients. Performance of serial measurements has been shown to be useful in guiding pharmacological therapy of portal hypertension and variceal hemorrhage. The technique is safe to perform; however, many patients are anxious and reluctant to undergo serial measurements. The effects of sedatives on portal pressure measurements have not yet been defined. The objective of this study was to evaluate the effects of midazolam on the HVPG. Twenty patients with compensated cirrhosis were included in this prospective, double-blind study. The HVPG was determined by subtracting the free hepatic venous pressure (FHVP) from the wedged hepatic venous pressure (WHVP). Patients were randomized to receive either placebo, 0.02 mg/kg midazolam, or 0.03 mg/kg midazolam, administered intravenously over 3 minutes. Immediately after drug administration and every 3 minutes thereafter, for a total of 30 or 40 minutes, measurements were repeated. Three hours later, patients were asked to state whether the sedative affected their state of comfort/relaxation. The effects of both doses of midazolam on HVPG did not differ significantly from those of placebo. Furthermore, neither dose of midazolam induced significant changes in HVPG as compared with baseline values. However, higher-dose midazolam (0.03 mg/kg) was associated with significant reductions in FHVP from baseline and a tendency for a reduction in WHVP. Both doses significantly increased patient comfort and relaxation during the test. Midazolam, used at a dose of 0.02 mg/kg, is effective in increasing patient comfort and relaxation during hepatic venous pressure measurements, without significantly affecting pressures (HVPG, WHVP, or FHVP). It is therefore an acceptable option for patients undergoing serial hepatic venous pressure measurements.

Neurotensin is a proinflammatory neuropeptide in colonic inflammation

The neuropeptide neurotensin mediates several intestinal functions, including chloride secretion, motility, and cellular growth. However, whether this peptide participates in intestinal inflammation is not known. Toxin A, an enterotoxin from Clostridium difficile, mediates pseudomembranous colitis in humans. In animal models, toxin A causes an acute inflammatory response characterized by activation of sensory neurons and intestinal nerves and immune cells of the lamina propria. Here we show that neurotensin and its receptor are elevated in the rat colonic mucosa following toxin A administration. Pretreatment of rats with the neurotensin receptor antagonist SR-48, 692 inhibits toxin A-induced changes in colonic secretion, mucosal permeability, and histologic damage. Exposure of colonic explants to toxin A or neurotensin causes mast cell degranulation, which is inhibited by SR-48,692. Because substance P was previously shown to mediate mast cell activation, we examined whether substance P is involved in neurotensin-induced mast cell degranulation. Our results show that neurotensin-induced mast cell degranulation in colonic explants is inhibited by the substance P (neurokinin-1) receptor antagonist CP-96,345, indicating that colonic mast activation in response to neurotensin involves release of substance P. We conclude that neurotensin plays a key role in the pathogenesis of C. difficile-induced colonic inflammation and mast cell activation.

Botulinum toxin injections for achalasia symptoms can approximate the short term efficacy of a single pneumatic dilation: a survival analysis approach

OBJECTIVE

Botulinum toxin injection can induce a temporary symptomatic remission in some patients with achalasia, but the comparative utility of the approach is not fully known. This study used survival analysis methods to better understand the ability of single or repeated botulinum toxin injections to postpone the need for other treatments.

METHODS

The response to botulinum toxin in 42 patients with idiopathic achalasia who had not received prior treatment was compared with the outcome in 26 consecutive patients who underwent initial treatment with pneumatic dilation. Survival analysis methods were employed using time to retreatment as the principal outcome measure.

RESULTS

Retreatment (any type) was required in 50% of subjects at 265 days (0.73 yr) after the first botulinum toxin injection. In contrast, retreatment after initial pneumatic dilation was required in <40% of patients after 2 and 5 yr of follow-up. The curves became significantly separated (p < 0.05) within 1 yr after initial treatment. Of those treated solely with botulinum toxin injections, repeated as needed, only 46% required pneumatic dilation or surgery by 2 yr. Survival analysis curves for repeated injections and initial pneumatic dilation did not differ statistically at 1 or 2 yr (p = 0.5 and p = 0.4, respectively). Correlational analyses indicated that, of the clinical parameters tested, only the degree of dysphagia for liquids was useful in selecting the better responders to botulinum toxin injections, with lesser symptoms predicting longer time to retreatment.

CONCLUSIONS

Botulinum toxin injections, repeated as needed, can approximate the benefits of a single pneumatic dilation for < or = 2 yr from the standpoint of usual factors that drive further management.

The role of epidermal growth factor (EGF) and its receptor in mucosal protection, adaptation to injury, and ulcer healing: involvement of EGF-R signal transduction pathways

Growth factors and their receptors are known to play important roles in normal cell proliferation, morphogenesis, tissue repair, and ulcer healing. Epidermal growth factor (EGF) inhibits acid secretion, exerts a trophic effect on gastroduodenal mucosa, protects gastric mucosa against injury, mediates mucosal adaptation, and accelerates gastroduodenal ulcer healing by stimulating cell migration and proliferation. EGF exerts its actions by binding to its receptor, EGF-R, a transmembrane protein tyrosine kinase, which triggers receptor dimerization, autophosphorylation, and recruitment of kinase substrates. These events result in Ras (GTP-binding protein) activation of the Ras/Raf/MAP kinase pathway, leading to phosphorylation of regulatory proteins and transcription factors and culminating in cell proliferation. Other pathways potentially activated by EGF include the phosphatidylinositol pathway and the JAK/STAT signaling pathway. Recent studies demonstrated that EGF-R-associated tyrosine kinase plays an essential role in regulating gastric mucosal cell proliferation after acute injury and further demonstrated activation of the EGF-R gene, EGF-R phosphorylation, and increased MAP kinase activity during early stages of experimental gastric ulcer healing. Finally, experimental data indicate that Helicobacter pylori vacuolating cytotoxin inhibits healing of experimental gastric ulcers, cell proliferation, binding of EGF to its receptor, EGF-induced EGF-R phosphorylation, and MAP kinase (ERK-2) activation. These H. pylori actions can explain its interference with the ulcer healing process.