Development of a sensitive molecular diagnostic assay for detecting Borrelia burgdorferi DNA from the blood of Lyme disease patients by digital PCR.

Lyme disease patients would greatly benefit from a timely, sensitive, and specific molecular diagnostic test that can detect the causal agent Borrelia burgdorferi at the onset of symptoms. Currently available diagnostic methods recommended by the Centers for Disease Control and Prevention for Lyme disease involve indirect serological tests that rely on the detection of a host-antibody response, which often takes more than three weeks to develop. With this process, many positive cases are not detected within a timely manner, preventing a complete cure. In this study, we have developed a digital polymerase chain reaction (PCR) assay that detects Lyme disease on clinical presentation with a sensitivity two-fold higher than that of the currently available diagnostic methods, using a cohort of patient samples collected from the Lyme disease endemic state of Connecticut, USA, in 2016-2018. Digital PCR technology was chosen as it is more advanced and sensitive than other PCR techniques in detecting rare targets. The analytical detection sensitivity of this diagnostic assay is approximately three genome copies of B. burgdorferi. The paucity of spirochetes in the bloodstream of Lyme disease patients has hindered the clinical adoption of PCR-based diagnostic tests. However, this drawback was overcome by using a comparatively larger sample volume, applying pre-analytical processing to the blood samples, and implementing a pre-amplification step to enrich for B. burgdorferi-specific gene targets before the patient samples are analyzed via digital PCR technology. Pre-analytical processing of blood samples from acute patients revealed that the best sample type for Lyme disease detection is platelet-rich plasma rather than whole blood. If detected in a timely manner, Lyme disease can be completely cured, thus limiting antibiotic overuse and associated morbidities.

Thrombosed cavernous hemangioma arising in cervical ectopic thymus tissue: a case report.

We report the case of a 35-year-old male presenting with a steadily growing, painful left-cervical neck mass. Final histopathologic diagnosis was consistent with a thrombosed cavernous hemangioma arising in cervical ectopic thymus tissue. This is the first description, to our knowledge, of such an entity.

Staged arterial embolization and surgical resection of a giant splenic artery aneurysm.

Splenic artery aneurysms (SAAs) are increasingly being diagnosed as incidental findings. Management modalities include operative treatment, percutaneous embolization, laparascopic ligation, and observation. Giant SAAs larger than 8 cm are a rare entity. We report the case of a 78-year-old woman with an 11 cm SAA who underwent successful percutaneous embolization, followed by surgical excision. We discuss the management of this patient and provide a review of the relevant literature. The approach to SAA should remain individualized.

Primary angiosarcoma of the lung.

Primary angiosarcoma of the lung is a rare disorder with few cases reported in the literature [Patel AM, Ryu JH. Angiosarcoma in the lung. Chest 1993;103:1531-35]. We present a case of primary angiosarcoma of the lung in a 79-year-old woman. Preoperative computed tomographic scan revealed soft tissue nodules surrounded by a halo of ground-glass attenuation, an appearance consistent with hemorrhagic pulmonary nodules [Primack S, Hartman T, Lee KS. Pulmonary nodules and the CT halo sign. Radiology 1994;190:513-15]. Lung biopsy revealed a multifocal malignant neoplasm with areas of hemorrhage. The histologic, cytologic, and immunophenotypic features were characteristic of epithelioid angiosarcoma. This case report contributes to the sparse literature on this disease and provides computed tomographic and pathologic correlation in a patient with hemorrhagic pulmonary nodules.

Tumor-to-tumor metastasis to a thyroid follicular adenoma as the initial presentation of a colonic adenocarcinoma.

The incidence of thyroid involvement by metastatic disease from distant organs ranges from an average of 3.1% in surgical series to 5.3% in autopsy series. However, the metastasis of one tumor into another (traditionally referred to as 'tumor-to-tumor metastasis') is distinctly uncommon. Typically, they are identified as new manifestations or necropsy findings of a known, pre-existing donor tumor. Herein is described the case of a 59-year-old woman whose thyroid nodule (a follicular adenoma) was resected and found to contain foci of a well-differentiated adenocarcinoma with a morphologic and immunohistochemical profile consistent with origination from the lower gastrointestinal tract. Subsequent diagnostic work-up revealed a sigmoid colon tumor with metastases to the liver. This is, to the authors' knowledge, the first reported example of a colon adenocarcinoma whose initial clinical manifestation was a metastasis to a thyroid neoplasm and only the third reported example of a colonic adenocarcinoma metastatic to a thyroid tumor. In a review of previously reported examples of tumor-to-tumor metastases involving a thyroid neoplasm as the recipient, the following features were present in the majority: (i) multifocality of the metastatic tumor aggregates; (ii) a total lack of, or only minimal amounts of reaction (desmoplastic, inflammatory or myxoid) of the recipient tumor to the metastatic deposits; and (iii) retention of the histopathologic characteristics of the donor tumor in the metastatic deposits. In general, strikingly divergent morphologic features in an otherwise typical thyroid neoplasm should elicit a differential diagnosis that takes into consideration the possibility of metastasis.