Siddique et al. Journal of Medical Case Reports 2011, 5:269 http://www.jmedicalcasereports.com/content/5/1/269 sweats. The rest of the review of the patient’s systems was unremarkable. His medical history included diabetes mellitus and hypertension. His social history was significant for smoking. He had quit alcohol intake five months before his presentation to our hospital. He denied any intrave- nous drug use, recent travel history or exposure to any people who were ill. He did not report any recent change in his medications and was tolerating his aspirin, sitagliptin, fosinopril, metformin and repaglinide without reported side effects. His physical examination was sig- nificant for pallor, icteric sclerae and non-tender hepato- megaly. His vital signs were normal. His body temperature was 98°F, his blood pressure was 125/78 mmHg, his pulse was 76 beats/minute and his respira- tory rate was 16 breaths/minute. The patient was admitted to the medical service for further work-up. A complete blood count was significant for pancytope- nia, with hemoglobin 8.9 g/dL, white blood cell count 3600/mm3 and platelet count 94,000/mm3. His chemis- try panel revealed hyperbilirubinemia, with total biliru- bin 10 mg/dL, direct bilirubin 7 mg/dL and only minimal elevation of transaminases (alanine transami- nase 74I U/L and aspartate transaminase 52I U/L). His alkaline phosphatase and g-glutamyl transferase levels were significantly raised at 293I U/L and 327I U/L, respectively. This profile is most consistent with obstructive jaundice. However, to rule out hepatocellular causes in this patient, we requested screens for hepatitis A immunoglobulin M (IgM) antibody, hepatitis B sur- face antigen, anti-nuclear antibodies, anti-smooth mus- cle antibodies, anti-mitochondrial antibodies, peri- nuclear anti-neutrophil cytoplasmic antibodies and human immunodeficiency virus 1/2 antibodies, and all serologies came back negative. The patient’s serum levels of a-fetoprotein and CA 19-9 were also found to be within normal limits. His coagulation profile and electrolytes were normal. About two weeks prior to presentation this patient had undergone magnetic resonance cholangiopancreati- cography at another hospital. The scans did not show any intra-or extra-hepatic biliary duct dilatation. Mag- netic resonance imaging of the liver with intravenous contrast enhancement done at our hospital revealed hepatomegaly. A right upper quadrant sonogram con- firmed the presence of hepatomegaly with increased par- enchymal echogenicity, suggestive of fatty infiltration or hepatocellular disease. These imaging studies did not show any evidence of intra-or extra-hepatic biliary duct dilatation and thus failed to fully explain the obstructive jaundice with a bilirubin level of 10 mg/dL (Figure 1). The patient’s pancytopenia was also further explored and was best attributed to the possibility of hypoproli- ferative marrow, as his reticulocyte production index Page 2 of 4 Figure 1 Magnetic resonance imaging scan of the liver with contrast enhancement obtained during the first week of admission showing a normal hepatobiliary tree. came back low (0.83), his direct Coombs test was nega- tive and his haptoglobin level was normal (262 mg/dL). However, interestingly, his lactate dehydrogenase level was raised (319I U/L). As his initial blood work and radiological investiga- tions were inconclusive, an ultrasound-guided core liver biopsy was performed. The histopathology revealed lym- phocytes infiltrating the hepatic parenchyma. His immu- nohistochemistry (IHC) was positive for CD45, CD10, terminal deoxynucleotidyl transferase (TdT), CD79A and PAX5 in the large cell infiltrate. CD20, CD3 and CD5 were negative in the infiltrate but were found to be positive in the rare small lymphocytes. Bcl2 was also faintly positive. CD117, CD23, pan-melanoma marker and pan-cytokeratin were all negative. The myeloid cell markers CD13, CD15 and myeloperoxidase were also negative. This IHC staining pattern was most compati- ble with a diagnosis of pre-B-cell ALL. Besides this evi- dence, his hepatic parenchyma showed changes consistent with bile stasis. The patient’s liver biopsy was thus suggestive of obstructive jaundice secondary to infiltration of liver parenchyma with leukemic cells. This work-up was followed by a bone marrow biopsy, which confirmed the diagnosis of pre-B-cell ALL. It showed > 90% cellularity with a diffuse, uniform infiltra- tion of lymphoid blasts that had prominent nucleoli. Normal cell lines (erythroid, myeloid and megakaryocy- tic) were markedly decreased. IHC staining was positive for CD34, CD10 and TdT. Rare small lymphocytes were positive for CD3, CD5 and CD20. His IHC was negative for CD117, CD23, cyclin D1 and myeloperoxidase. Flow cytometric immunophenotypic analysis of his bone mar- row aspirate revealed 62% lymphoblasts in the bone marrow, with the following phenotypes: CD34-positive, TdT-positive, CD19-positive, CD79a-positive, CD10-