Pneumocystis carinii involvement of the liver and spleen: CT demonstration

A Rare Case of Splenic Pneumocystis jirovecii in a HIV-Positive Patient

Introduction

Human immunodeficiency virus (HIV) positive individuals with the CD4 count less than 200 cells/mm³ are at risk for opportunistic infections. Pneumocystis jirovecii, a fungal pathogen, is a common cause of opportunistic infections with predominantly pulmonary involvement. Disseminated P. jiroveciii infection presenting with hepatosplenic lesion is extremely rare. Case Summary. A 31-year-old male with HIV with and acquired immunodeficiency syndrome (AIDS) presented with diarrhea for 3 weeks. He had splenomegaly and inguinal lymphadenopathy on physical examination. Laboratory parameters revealed anemia and hypoalbuminemia, while stool studies for infectious etiology and fecal leucocyte were negative. Computed tomography (CT) of the chest and abdomen depicted consolidation of the lungs and a large splenic mass. He underwent fiberoptic bronchoscopy with transbronchial biopsy which was consistent with P. jirovecii pneumonia. He also had a ultrasound-guided core biopsy of the splenic mass which revealed necrotizing granulomas with Pneumocystis jirovecii infection on Grocott-Gomori's methenamine silver (GMS) stain and was initiated on treatment for P. jirovecii with sulfamethoxazole with trimethoprim.

Conclusion

Malignancy and atypical infection are key differentials in patients presenting with hepatosplenic lesions. HIV positive patients are at increased risk of AIDS-related lymphoma. Tissue diagnosis is often required for further evaluation. Disseminated P. jirovecii presenting with splenic mass and liver lesion is extremely rare.

Littoral cell angioma (LCA) associated with liver cirrhosis

A littoral cell angioma (LCA) is a rare benign vascular tumor of the spleen. A 60-year-old man, with multiple nodules in imaging study and liver cirrhosis graded as Child-Pugh classification class A, was transferred for splenomegaly. A thrombocytopenia was found on hematological evaluation. Because there was no evidence of hematological and visceral malignancy, a splenectomy was performed for a definitive diagnosis. The histological and immunohistochemical features of the splenic specimens were consistent with a LCA. After the splenectomy, the thrombocytopenia recovered to the normal platelet count. There has been no previous report of a LCA combined with liver cirrhosis. Herein, the first case of a LCA in Korea, diagnosed and treated by a splenectomy, is reported.

Littoral cell angioma of the spleen: CT features with clinicopathologic comparison

PURPOSE

To evaluate the clinical, pathologic, and computed tomographic (CT) features of littoral cell angioma of the spleen in eight patients.

MATERIALS AND METHODS

Two abdominal radiologists retrospectively reviewed the contrast material-enhanced CT images obtained in six, the contrast-enhanced and nonenhanced CT images obtained in two, and the photographs of gross pathologic specimens resected from seven patients. They also retrospectively reviewed clinical data (ie, demographic data, presenting signs and symptoms, physical findings, and medical histories). Histopathologic specimens from the eight patients were reviewed by a hematopathologist. The CT images were reviewed for the presence of splenomegaly. The number, size, and enhancement characteristics of the splenic masses at CT were compared with the histopathologic and gross pathologic specimen findings.

RESULTS

All patients had laboratory evidence of hypersplenism. Seven patients (88%) had splenomegaly and innumerable splenic masses ranging from 0.2 to 6.0 cm in diameter at CT. The single patient with a normal spleen size had four splenic masses. The splenic masses were hypoattenuating relative to the normal spleen at CT in all patients and correlated with blood-filled nodules at gross pathologic examination and with blood-filled vascular channels of littoral cell angioma at histopathologic examination. The early and late portal venous phase CT images that were available in one case demonstrated progressive homogeneous contrast enhancement of the masses such that they were indistinguishable from the normal splenic parenchyma.

CONCLUSION

Littoral cell angioma is a primary splenic neoplasm that most commonly manifests at CT as multiple hypoattenuating masses in an enlarged spleen. Histopathologically, these masses represent blood-filled vascular channels.

Hepatobiliary and pancreatic infections in AIDS: Part one

Infections of the liver and biliary tract are common during the course of AIDS. A variety of viral, bacterial, fungal, and other opportunistic infections can present with hepatobiliary involvement as either the primary site of infection or secondary to a disseminated process. Coinfection with hepatitis B and C are particularly common due to the shared means of transmission of these viruses with HIV. The typical presenting features of hepatobiliary infections are right upper quadrant (RUQ) pain and abnormal liver function tests. Initial evaluation should include an RUQ ultrasonogram, which will usually identify abnormalities in the biliary tract and may demonstrate some parenchymal abnormalities as well. A liver biopsy is necessary to determine the etiology of focal hepatic lesions or opportunistic infections within hepatic parenchyma when other less invasive tests are negative or inconclusive. Special stains and culture techniques are required to identify specific organisms in the biopsy specimen. HIV-related biliary disorders include acalculous cholecystitis, which is a potentially serious condition requiring prompt recognition and gallbladder decompression. AIDS-cholangiopathy is a form of cholangitis involving the intra- and/or extrahepatic biliary tree. Endoscopic retrograde cholangio-pancreatography (ERCP) is the test of choice, demonstrating the stricturing, dilatation, and beading of bile ducts seen in this condition. Endoscopic sphincterotomy of the papilla of Vater may provide symptomatic relief for patients with papillary stenosis. Opportunistic infections of the pancreas have been reported. Evaluation should include a computerized tomogram of the abdomen and possible pancreatic tissue aspiration or biopsy. Management of pancreatitis is supportive.

Identification of extrapulmonary Pneumocystis carinii in immunocompromised rats by PCR

Pneumocystis carinii has been shown to cause extra-alveolar infections in humans, but the lack of a reproducible animal model has hindered the elucidation of mechanisms of P. carinii dissemination. In the present study, PCR and the immunosuppressed rat model were used to gain further insight into the dissemination of P. carinii organisms in extrapulmonary (EP) tissues. Primer sequences specific to major surface glycoprotein (MSG) and dihydrofolate reductase (DHFR) were used to detect P. carinii in lungs and EP tissues. Sprague-Dawley rats were grouped into two classes: one group included rats that had primary episodes of pneumocystosis and the other group included rats that had undergone treatment for P. carinii infection and that had second episodes of pneumocystosis. PCR analysis with MSG primers with tissues obtained from both groups of rats showed the presence of P. carinii DNA in adrenal tissue, bone marrow, blood, and heart, kidney, liver, lymph node, spleen, and thyroid tissues. Reverse transcriptase-PCR (RT-PCR) analysis was carried out with DHFR primers with lung, spleen, heart, kidney, and liver tissues from both groups of rats. Only those tissues that showed a positive PCR result and hybridization signal for the MSG gene were used for the RT-PCR experiments. RT-PCR analysis showed that the P. carinii DHFR gene is actively transcribed in these tissues, thereby indicating the presence of viable P. carinii organisms in EP tissues. Our observations suggest that P. carinii dissemination is influenced by factors other than P. carinii chemotherapy and that heavy organism load and destruction of lung tissue may contribute to the dissemination of P. carinii. The study provides an animal model that can be used for further investigations of the causes of EP pneumocystosis.

Disseminated Pneumocystis carinii infection involving the neck and nasopharynx

In summary, several points should be emphasized: 1. Adenoidal hypertrophy in a person who previously underwent adenoidectomy should lead to the suspicion of HIV infection. 2. P. carinii should be included in the differential diagnosis of adenoidal enlargement in HIV infections. 3. Extrapulmonary calcification should lead to the suspicion of P. carinii infection.