Prognostic factors for the survival of patients with AIDS cholangiopathy

Concomitant AIDS cholangiopathy and Fanconi syndrome as complications of HIV in a single patient

We describe the case of a 50-year-old woman presenting to our acute medicine department with generalised non-specific symptoms on a background of HIV managed on triple therapy (tenofovir, lamivudine and zidovudine). On admission, she was noted to be acidotic with proteinuria, glycosuria, hypophosphataemia and generalised body pain, and was diagnosed with Fanconi's renotubular syndrome secondary to tenofovir. It was also noted that she had elevated liver dysfunction markers, and an MRI of the liver revealed a focal stricture near the ampulla of Vater, resulting in a diagnosis of AIDS cholangiopathy. These two diagnoses are rare complications of HIV, and the presence of both these pathologies in a single patient has never been reported in the literature before, and we therefore believe that this case is the first of its kind.

Chronic liver disease in the human immunodeficiency virus patient

There are an estimated 40 million HIV infected individuals worldwide, with chronic liver disease being the 2nd leading cause of mortality in this population. Elevated liver functions are commonly noted in HIV patients and the etiologies are varied. Viral hepatitis B and C, fatty liver and drug induced liver injury are more common. Treatment options for viral hepatitis C are rapidly evolving and are promising, but treatments are limited for the other conditions and is primarily supportive. Opportunistic infections of the liver are now uncommon. Irrespective of etiology, management requires referral to specialized centers and with due diligence mortality can be reduced.

Biliary manifestations of systemic diseases

Patients with a variety of systemic diseases may present with clinical indications of biliary tract disorders. This article describes a group of systemic conditions associated with bile duct abnormalities and the role of endoscopic therapy in their diagnosis and management.

Challenges in understanding the immunopathogenesis of Cryptosporidium infections in humans

Water and foodborne enteric cryptosporidiosis is a globally emerging public health issue. Although the clinical manifestations of enteric cryptosporidiosis are generally limited to intestinal infection and subsequent diarrhoea, extra-intestinal invasion has also been diagnosed in immunocompromised individuals, particularly in those infected with human immunodeficiency virus (HIV) or AIDS. Due to an inadequate understanding of Cryptosporidium immunopathogenesis in humans, the development of vaccines or therapeutic agents and their application in diseases management is difficult. Current therapeutic measures are not fully effective in the treatment of the disease. Therefore, the implementation of strategies designed to control the chain of cryptosporidiosis transmission (environment ↔ human ↔ food/water ↔ animal) is a critical but challenging issue to public health authorities across the world. Several excellent studies have been done on innate, acquired and mucosal immunity against Cryptosporidium infections using animal models, in vitro human cell lines and human volunteers. However, there are still multiple challenges in understanding the intestinal immune response (immunopathogenesis) to Cryptosporidium infection in humans. This paper reviews recent updates on immunopathogenesis and immune responses to Cryptosporidium infection in humans, while also discussing the current limitations that exist regarding a precise understanding of the immunopathological mechanisms.

AIDS Cholangiopathy in an Asymptomatic, Previously Undiagnosed Late-Stage HIV-Positive Patient from Kenya

AIDS-associated cholangiopathy is a form of biliary tract inflammation with stricture formation seen in AIDS patients who are severely immunosuppressed. It is no longer common in countries in which HAART therapy is widely employed but is still seen in underdeveloped countries. The majority of patients are symptomatic at the time of presentation. Herein, we describe a seventy-four-year-old woman who presented with unilateral leg swelling after a prolonged airplane flight. She was otherwise entirely asymptomatic. Routine laboratory testing was notable for a hypochromic microcytic anemia, slight leukopenia, and mild hypoalbuminemia. Liver enzymes were all elevated. Deep venous thrombosis was confirmed, and a CT scan of the chest disclosed no pulmonary emboli. However, the visualized portion of the abdomen showed dilatation of the common bile and pancreatic ducts. This was confirmed on ultrasonography and MRCP, and no obstructive lesions were noted. An ERCP revealed a dilated common bile duct without filling defects or strictures. A balloon occlusion cholangiogram showed strictures and beading of the intrahepatic ducts. Shortly thereafter, serology for HIV returned positive along with a depressed CD4 cell count, and the patient was diagnosed with AIDS-associated cholangiography.

Liver disease in the HIV-infected individual

Since the advent of effective antiretroviral therapy (ART) for human immunodeficiency virus-1 (HIV), there has been a substantial decrease in deaths related to acquired immunodeficiency syndrome (AIDS). However, in the ART era, liver disease is now the most common non-AIDS-related cause of death among HIV-infected patients, accounting for 14%-18% of all deaths in this population and almost half of deaths among hospitalized HIV-infected patients. Just as the burden of non-AIDS morbidity and mortality has changed in the ART era, the types of liver disease the clinician is likely to encounter among these patients have changed as well. This review will discuss the causes of liver disease in the HIV-infected population in the ART era, including chronic hepatitis C virus, chronic hepatitis B virus, medication-related hepatotoxicity, alcohol abuse, nonalcoholic fatty liver disease, and AIDS-related liver diseases.

HIV/AIDS cholangiopathy: clinical spectrum, cholangiographic features and outcome in 30 patients

BACKGROUND AND AIMS

AIDS cholangiopathy is presently considered rare and has been reported mainly from the West. With the HIV epidemic in India, we have encountered an increasing number of patients. We aimed to study these patients and determine differences from earlier experiences.

METHODS

We describe the clinical presentation, cholangiographic features, and outcome and determine differences reported in Western literature.

RESULTS

From Jan 1999 to May 2009, 30 patients (27 men) with AIDS cholangiopathy were seen. The most common mode of transmission was heterosexual (n = 28) followed by blood transfusion (n = 2). Abdominal pain (n = 20) of biliary origin, was the commonest manifestation followed by an asymptomatic group (n = 6) and a third group (n = 3) with pain due to pancreatitis. Ultrasonography of the abdomen was abnormal in all patients. Papillary stenosis (n = 23) was the most common cholangiographic feature followed by sclerosing cholangitis (n = 5). Abdominal pain resolved reliably and promptly after endoscopic sphincterotomy. Cholangiographic abnormalities regressed during follow up on antiretroviral therapy in 10 patients. Seven patients on anti retroviral therapy developed de novo cholangiopathy, with a precipitous drop in CD4 count of whom two had a worse prognosis. None had Kaposi's sarcoma.

CONCLUSIONS

In contrast to Western literature, HIV cholangiopathy was seen predominantly in patients who acquired HIV by heterosexual transmission. De novo development of cholangiopathy on antiretroviral therapy may indicate the occurrence of resistance. Papillary stenosis is the most common feature. Abdominal pain resolved with sphincterotomy. Regression of cholangiographic abnormality occurred with anti retroviral medications. Median survival following cholangiopathy diagnosis was 34 months, higher than reported in previous studies.

HIV-1 Tat protein suppresses cholangiocyte toll-like receptor 4 expression and defense against Cryptosporidium parvum

Biliary cryptosporidiosis is associated with acquired immunodeficiency syndrome (AIDS) cholangiopathy and occurs almost exclusively in adult patients with AIDS. Infection of biliary epithelial cells (cholangiocytes) with Cryptosporidium parvum induces Toll-like receptor (TLR) 4 expression and stimulates a TLR-dependent response against infection. Here, we tested whether human immunodeficiency virus type 1 (HIV-1) Tat affects TLR expression and, hence, anti-C. parvum defense responses. Using an in vitro model of human biliary cryptosporidiosis, we found that recombinant Tat protein increased TLR4 mRNA expression in both uninfected and C. parvum-infected cholangiocytes. Conversely, Tat decreased TLR4 protein levels and suppressed C. parvum-induced TLR4 protein expression. Using actinomycin to inhibit transcription, we found that Tat increased the half-life of TLR4 mRNA from approximately 25 to 60 min, and RNA gel-shift assays demonstrated direct binding of Tat to TLR4 mRNA. In vitro transcription/translation studies suggested that Tat does not affect transcription but does decrease TLR4 translation. Importantly, more parasites were found in Tat-treated cells than in control cells 48 h after infection. These findings suggest that Tat inhibits cholangiocyte TLR4 protein expression through translational inhibition. These events appear to diminish the ability of cholangiocytes to initiate an innate immune response to C. parvum. We suggest that these findings may contribute to the unusual susceptibility of HIV-infected individuals to biliary cryptosporidiosis.

Gastrointestinal cytomegalovirus disease in the immunocompromised patient

Cytomegalovirus (CMV) has emerged as a significant opportunistic pathogen in the era of immunosuppression. CMV was a common cause of gastrointestinal disease in AIDS patients, but the introduction of highly active antiretroviral therapy has led to a dramatic decline in AIDS-related disease. Among patients with solid organ transplants, CMV has become an increasingly important cause of gastrointestinal disease as more routine use of early CMV prophylaxis has increased delayed-onset disease, which is often tissue invasive at presentation. The role of CMV in inflammatory bowel disease is controversial; treatment may be indicated in selected cases of steroid-refractory disease with evidence of CMV. Diagnosis of gastrointestinal CMV disease generally requires endoscopic biopsy with histologic confirmation. CMV culture of biopsy material may be falsely positive because of contamination from latently infected cells. The standard induction treatment of gastrointestinal CMV disease uses intravenous ganciclovir, though the use of oral valganciclovir is increasing, especially for long-term maintenance or suppression therapy.

Article Commentary: Occupational Risks of Blood Exposure in the Operating Room

Bloodborne pathogens continue to be a source of occupational infection for healthcare workers, but particularly for surgeons. Over 1 per cent of the U.S. population has one or more chronic viral infections. Hepatitis B is the infection that has the longest known role as an occupational pathogen, but infection with this virus is largely preventable with the use of the effective hepatitis B vaccine. Hepatitis C affects the largest number of people in the United States, and there is no vaccine available for the prevention of this infection. HIV infection still has not been associated with a documented transmission in the operating room environment, but six cases of probable occupational transmission have been reported. A total of 57 healthcare workers have had documented occupational infection since the epidemic of HIV infection began. Infection of blood-borne pathogens to patients from infected surgeons remains a concern. Surgeons who are e-antigen-positive for hepatitis B have been well documented to be an infection risk to patients in the operating room. Only four surgeons have been documented to transmit hepatitis C, although other transmissions have occurred in the care of patients when practices of infection control have been violated. No surgical transmission of HIV to a patient has been identified at this time. Prevention of occupational infection requires use of protective barriers, avoidance of exposure risk by modification of techniques, and a constant awareness of sharp instruments in the operating room. Blood exposure in the operating room carries risk of infection and should be avoided. It is likely that other infectious agents will emerge as operating room threats. Surgeons must maintain vigilance in avoiding blood exposure and percutaneous injury.

The human immunodeficiency virus type 1 tat protein enhances Cryptosporidium parvum-induced apoptosis in cholangiocytes via a Fas ligand-dependent mechanism

While Cryptosporidium parvum infection of the intestine has been reported in both immunocompetent and immunocompromised individuals, biliary infection is seen primarily in adult AIDS patients and is associated with development of AIDS cholangiopathy. However, the mechanisms of pathogen-induced AIDS cholangiopathy remain unclear. Since we previously demonstrated that the Fas/Fas ligand (FasL) system is involved in paracrine-mediated C. parvum cytopathicity in cholangiocytes, we also tested the potential synergistic effects of human immunodeficiency virus type 1 (HIV-1) transactivator of transcription (Tat)-mediated FasL regulation on C. parvum-induced apoptosis in cholangiocytes by semiquantitative reverse transcription-PCR, immunoblotting, immunofluorescence analysis, and immunogold electron microscopy. H69 cells do not express CXCR4 and CCR5, which are receptors required for direct HIV-1 viral infection. However, recombinant biologically active HIV-1-associated Tat protein increased FasL expression in the cytoplasm of cholangiocytes without a significant increase in apoptosis. We found that C. parvum-induced apoptosis was associated with translocation of intracellular FasL to the cell membrane surface and release of full-length FasL from infected H69 cells. Tat significantly (P < 0.05) increased C. parvum-induced apoptosis in bystander cells in a dose-dependent manner. Moreover, Tat enhanced both C. parvum-induced FasL membrane translocation and release of full-length FasL. In addition, the FasL neutralizing antibody NOK-1 and the caspase-8 inhibitor Z-IETD-fmk both blocked C. parvum-induced apoptosis in cholangiocytes. The data demonstrated that HIV-1 Tat enhances C. parvum-induced cholangiocyte apoptosis via a paracrine-mediated, FasL-dependent mechanism. Our results suggest that concurrent active HIV replication, with associated production of Tat protein, and C. parvum infection synergistically increase cholangiocyte apoptosis and thus jointly contribute to AIDS-related cholangiopathies.

Growing importance of liver disease in HIV-infected persons

Liver disease is a growing problem in HIV-infected persons. In those who are able to take antiretroviral therapy, the forms of liver disease have changed and their relative importance has increased. This review focuses on liver disease in HIV-infected persons, caused by hepatitis C virus, hepatitis B virus, or treatment of HIV infection.

Efficacy of nitazoxanide and paromomycin in biliary tract cryptosporidiosis in an immunosuppressed gerbil model

OBJECTIVES

To evaluate the efficacy of nitazoxanide and paromomycin in biliary tract cryptosporidiosis in an immunosuppressed Mongolian gerbil (Meriones unguiculatus) model.

METHODS

Gerbils (1-month-old) were dexamethasone-immunosuppressed for 10 days and challenged orally with 10(5) Cryptosporidium parvum oocysts. From day 0 to day 12 post-infection, one group (n=14) was treated with 200 mg/kg/day nitazoxanide and another (n=15) with 100 mg/kg/day paromomycin. Infection and efficacy of nitazoxanide and paromomycin were assessed by measuring oocyst shedding in faeces, biliary tract and ileum histological examination.

RESULTS

In nitazoxanide-treated and paromomycin-treated groups as compared with untreated animals (P<0.05), oocyst shedding was partially suppressed in a similar manner (P>0.05). Parasites were present in histological sections of the ileal mucosa of 16/16 infected untreated animals versus 3/14 and 6/15 in the nitazoxanide-treated and the paromomycin-treated groups, respectively (P<0.05). In addition, gall bladder infection was less frequent in nitazoxanide-treated (2/14, P<0.01) and paromomycin-treated (5/15, P=0.07) animals than in untreated controls (9/16). No histological alteration of biliary mucosa was observed in both treated and untreated infected gerbils.

CONCLUSIONS

Present data support the efficacy of nitazoxanide and, to a lesser extent, paromomycin on biliary C. parvum infection in gerbils, and prompt further investigation of the potential clinical benefits of nitazoxanide in treating human biliary cryptosporidiosis.

The Liver in HIV in Africa

As access to antiretroviral therapy improves across the African continent, liver disease is emerging as an important cause of morbidity and mortality among HIV-infected individuals. Although coinfection with hepatitis B virus (HBV) and hepatitis C virus (HCV), along with highly active antiretroviral therapy (HAART)-induced hepatotoxicity appear to be the major causes of liver disease in this population, other diseases endemic to Africa with hepatic manifestations are influenced by HIV infection as well. In this review we present the available data on liver disease in HIV-infected populations in Africa and discuss relevant data from the rest of the world. In addition, we highlight important areas for further study.

Hemobilia caused by cytomegalovirus cholangiopathy

A 57-yr-old male on long-term steroid therapy presented with hematemesis, fever, and a retroperitoneal fluid collection. Hemobilia was diagnosed, but the cause was not identified by ERCP, computed tomography, or angiography. Peroral cholangioscopy revealed multiple biliary ulcers. Cholangioscopic biopsies diagnosed cytomegalovirus (CMV) infection. Intravenous ganciclovir therapy was initiated, and was associated with cessation of bleeding. Biliary CMV disease is rare in HIV-negative persons, but should be considered in a patient with unexplained hemobilia. Cholangioscopy may be useful for diagnosis.

AIDS cholangiopathy

AIDS is an advanced disease with systemic and infectious complications that can be fatal. When a patient with AIDS presents with right upper quadrant or midepigastric pain, cholestasis, and symptoms of cholangitis, AIDS cholangiopathy should be suspected and appropriate diagnostic and therapeutic interventions should be initiated. Opportunistic infections such as Cryptosporidium and cytomegalovirus are the most common cause of AIDS cholangiopathy. Four distinct cholangiographic abnormalities have been demonstrated by endoscopic retrograde cholangiopancreatography, the most common being papillary stenosis with sclerosing cholangitis. Antimicrobial therapy is often ineffective. Highly active antiretroviral therapy may enhance immune function and offers the best medical therapy to clear the opportunistic infections. Ursodeoxycholic acid has a limited benefit in patients with sclerosing cholangitis and cholestasis. Endoscopic sphincterotomy has been shown to relieve pain and biliary obstruction in patients with papillary stenosis. Balloon dilation of strictures and stent placement decompress the biliary system and may be helpful. Cholecystectomy is recommended to treat acalculous cholecystitis, and celiac plexus block may be offered to patients with terminal disease and intractable abdominal pain.