Squamous metaplasia of extrahepatic biliary system in an AIDS patient with cryptosporidia and cholangitis

Pronounced squamous cell contamination in biliary tract cytology: A diagnostic pitfall

Squamous cells are rarely found in biliary tract cytology specimens, and when present are typically scant in quantity. Over an 8-year time period, two cases at our institution reporting abundant squamous cells were identified. Both patients underwent endoscopic retrograde cholangiopancreatography with bile duct brushings and removal of a migrated biliary stent. The migrated stents were retrieved using rat toothed forceps and required removal of the endoscope through the esophagus with the stent exposed to esophageal and oral mucosa outside of the endoscope. Cytologic examination of the accompanying biliary stent material accordingly revealed abundant benign squamous cells. However, bile duct brushings showed benign ductal epithelial cells without squamous cells. Prior and subsequent cytology and bile duct surgical pathology specimens did not show squamous metaplasia. Migrated biliary stents that require endoscopic withdrawal increase the risk of contaminating samples with squamous cells. Recognition of this unique scenario is important, as the differential diagnosis includes squamous metaplasia and squamous neoplasia.

Inherited and acquired clinical phenotypes associated with neuroendocrine tumors

PURPOSE OF REVIEW

Overview of neuroendocrine neoplasms in the context of their associations with primary and secondary immunodeficiency states.

RECENT FINDINGS

Malignancies of neuroendocrine origin are well known to be associated with hereditary syndromes, including multiple endocrine neoplasia type 1, von Hippel-Lindau syndrome, neurofibromatosis type 1, and tuberous sclerosis. This review includes the X-linked form of hyper-IgM syndrome (XHIGM), due to mutations in the CD40Ligand gene (CD40LG), as an additional inherited disorder with susceptibility to such malignancies, and discusses neuroendocrine tumors (NETs) arising in other immunocompromised states. Of all primary immune deficiency diseases, NETs appear to be unique to XHIGM patients. Outcomes for XHIGM patients with NETs is poor, and the mechanism behind this association remains unclear. In secondary immune deficiency states, NET occurrences were primarily in patients with HIV or AIDS, the autoimmune disease systemic lupus erythematosus and solid organ transplant recipients. Gastroenteropancreatic NETs were most frequent in XHIGM patients, whereas nongastroenteropancreatic-NETs, like Merkel cell carcinoma and small-cell lung carcinoma, affected HIV/AIDS patients. Possible mechanisms as to the nature of these associations are discussed, including chronic infections and inflammation, and CD40-CD40L interactions. Many questions remain, and further studies are needed to clarify the predisposition of patients with XHIGM to the development of NETs. Given that many of these patients present late in their disease state and have poor outcomes, it is imperative to keep a high index of suspicion at the advent of early signs and symptoms. Regular monitoring with laboratory or imaging studies, including tumor markers, may be warranted, for which further studies are needed.

SUMMARY

Of all primary immunodeficiency diseases, NETs appear to be unique to XHIGM, and the mechanism behind this association remains unclear. Outcome for XHIGM patients with NETs is poor, and it is imperative to keep a high index of suspicion at the advent of early signs and symptoms.

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 children with primary immunodeficiencies

OBJECTIVE

To investigate clinical features and to establish optimal management in children with primary immunodeficiency (PID) and liver disease. Study design A retrospective analysis of medical records of 147 children with PID who presented with abnormal liver tests to a tertiary center.

RESULTS

Clinical evidence of liver disease was documented in 35 (23.8%) patients. Of these, 22 (63%) had hepatomegaly and 14 (40%) had splenomegaly. Sclerosing cholangitis (SC) was diagnosed in 21 children (60%), based on radiological and histological criteria; 4 patients with SC on cholangiography had no biliary changes in the liver biopsy. Ultrasonography demonstrated a dilated biliary system in 14 (67%) children with SC. Of 27 children investigated for Cryptosporidium parvum (CSP), 12 (44%) were positive, including 9 of 12 with SC. Overall, 7 (20%) patients died, including 3 boys with disseminated recurrent CSP infection after successful liver transplantation (LT). Temporary deterioration of liver injury was observed in 2 CSP-positive boys with CD40 ligand deficiency (CD40LD) who were undergoing nonmyeloablative hematopoietic stem cell transplantation (HSCT). Successive liver and HSCT was curative in 1 patient with CD40LD and end-stage liver disease.

CONCLUSION

SC is the most common hepatic complication of PID. Mild liver involvement could be arrested by early nonmyeloablative HSCT, whereas advanced disease may warrant combined liver and HSCT.

Diarrhea and gallbladder hydrops in an immunocompetent child with Cryptosporidium infection

We report a case of an immunocompetent child who developed gallbladder hydrops during a concurrent diarrheal illness caused by Cryptosporidium parvum. Hepatobiliary disease and chronic cryptosporidial diarrhea is an accepted association in adults with HIV infection but has only once previously been reported in a child, also with HIV.

Cholangiopathy in HIV-infected patients

HIV cholangiopathy is a disease of advanced-stage AIDS that presents with biliary symptoms and anicteric cholestasis. An abnormal ultrasound examination in a patient with low CD4 count is evaluated by endoscopic retrograde cholangiopancreatography, which demonstrates the characteristic cholangiographic abnormalities. Besides being the gold standard for diagnosis, it offers therapeutic intervention and possible pain relief in the presence of papillary stenosis. An infectious pathogen is identifiable in a majority of patients, suggesting infection-related damage to the biliary tree. Anti-infective therapy, however, usually is ineffective, and prognosis is related to the underlying stage of AIDS.

Characterization and growth regulation of a rat intrahepatic bile duct epithelial cell line under hormonally defined, serum-free conditions

Bile duct epithelial cells, or cholangiocytes, proliferate in vivo under a number of pathologic (i.e., partial hepatectomy) and pathophysiologic (i.e., bile duct ligation, malignant transformation) conditions. However, little is known about the possible growth factors that modulate these proliferative responses, in part because an in vitro model to study proliferation of nontransformed, normal cholangiocytes is not available. We report here the development of a rat cholangiocyte cell line (MMRC, minimal media-requiring rat cholangiocytes) that grows under hormonally defined, serum-free conditions on plastic and maintains a cholangiocyte phenotype. Morphologic as well as functional studies indicate that the cell line is polarized and actively transports fluid and electrolytes in an apical to basolateral direction. MMRC, when cultured for 24 mo. and passaged 80 times, have not undergone malignant transformation, because the cell line failed to grow under anchorage-independent conditions or in nude mice. Cellular proliferation is accelerated 2-8-fold by insulin, insulin-like growth factor 1, epidermal growth factor, and hepatocyte growth factor, growth factors known to stimulate tyrosine kinase receptors, and inhibited 2-10-fold by TGFbeta and IL-2. Glyco-conjugates of primary (i.e., cholic and chenodeoxycholic acid) and secondary bile acids (i.e., deoxycholic and lithocholic acid) do not alter proliferation at low concentration (1 microM), but are toxic at higher concentration (10 microM). In summary, we have developed and characterized a cholangiocyte cell line derived from normal rat liver, which grows under hormonally defined, serum-free conditions, maintains a nonmalignant, cholangiocyte phenotype, displays morphologic and functional features of polarity, and alters its proliferation rate in response to a variety of growth factors.