Peritoneal Chlamydia trachomatis Infection as a Cause of Ascites: A Diagnosis Not to Be Missed

Ascites is a common complication of several conditions, but it is rare in cases of <i>Chlamydia trachomatis</i> infection. We report a 36-year-old patient presenting with abdominal swelling for a week prior to hospitalization. An extensive workup excluded liver or heart disease and malignancy. A computed tomography scan demonstrated massive ascites and severe thickening of peritoneal reflections. Laboratory tests showed low serum-ascites albumin gradient, high total protein, and low adenosine. Diagnostic laparoscopy revealed inflammatory signs of both fallopian tubes. The histopathological results from peritoneal biopsy were consistent with lymphoid proliferation with reactive lymphoplasmacytic infiltrate. A gynecological investigation showed a positive DNA for <i>C. trachomatis</i> in the cervical swab. After treatment with doxycycline, there was a complete resolution of ascites.

Case 38

Post-transplant lymphoproliferative disease (PTLD) is a disorder of lymphoid proliferation seen in recipients of solid organ or haematopoietic transplants as a consequence of immunosuppression. A spectrum of disease is recognized ranging from non-malignant polyclonal proliferation of B cells to monoclonal proliferation of B or T lymphocytes which have features in common with lymphomas. Epstein–Barr virus (EBV) is associated with a majority of cases although it is not a universal feature. Treatment with anti-CD20 antibody in addition to reduction in immunosuppression has become the most common treatment approach.

Synchronous Oncocytic Papillary Cystadenoma and Warthin Tumor of the Parotid Gland

Warthin tumor (WT) is the second most common benign salivary gland neoplasm. It is also the most frequent salivary gland tumor to occur synchronously or metachronously with another salivary gland neoplasm, in the same gland or on the other side. Oncocytic papillary cystadenomas (OPCs) are rare neoplasms that are more common in minor salivary gland locations and in women. We describe in detail the case of a 73-year-old male smoker with synchronous OPC and WT of the parotid gland. On microscopy, both tumors resembled each other considerably, with the only difference being that the OPC lacked the tumor-associated lymphoid proliferation characteristic of WT. These findings highlight that OPC bears considerable similarity to WT. While this morphological similarity may lead to misdiagnosis on rare occasions, it does not affect patient management, as clinical behavior of both these tumors is similar.

Utility of Flow Cytometry in the Diagnostic Evaluation of Recurrent or Persistent Nodular Lymphocyte-Predominant Hodgkin Lymphoma

Objectives We previously reported that lymph nodes involved by nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) had unique flow cytometric features. To further validate their diagnostic utility, we have examined the flow cytometry features in cases of persistent lymphadenopathy (LAD) prior to the diagnosis of NLPHL or recurrent LAD following diagnosis and treatment for NLPHL. Methods We retrospectively identified nine patients (2-3 specimens per patient for a total of 20 specimens) with persistent or recurrent lymphadenopathy before or after they were diagnosed with NLPHL between the ages of 13 and 76 years. Their histopathology diagnoses were reviewed and flow cytometry data were reanalyzed. Results Based on our published criteria (Am J Clin Pathol 2016;145:107-115), positive flow cytometry findings (at least 12% of T cells expressing CD57 or at least 3% of T cells coexpressing CD4 and CD8) were seen in 18 specimens. Based on histopathology, 11 of them were correctly diagnosed as NLPHL, 3 of them initially underdiagnosed as atypical lymphoid proliferation, and 4 of them initially incorrectly diagnosed as negative or progressive transformation of germinal centers (PTGCs). The flow cytometry studies showed similar expression patterns of CD57, CD4, and CD8 in T cells and very similar high percentages of CD57+ T cells and CD4+CD8+ T cells between initial biopsies and subsequent biopsies in these patients. Negative flow cytometry findings were seen in two specimens pathologically confirmed as negative for NLPHL in two patients after treatment. Their initial diagnostic specimens showed positive flow cytometry findings, different from that seen in the subsequent specimens posttreatment. Conclusion Flow cytometry appears to be a useful adjunct in detecting early or relapsed NLPHL, especially in atypical lesions. The presence of positive flow cytometry features is very sensitive in detecting recurrent or persistent NLPHL, while absence of positive flow cytometry features helps rule out NLPHL.