Deshka S. Foster

Evaluation of three rapid diagnostic tests for the detection of human infections with Plasmodium knowlesi

BackgroundPlasmodium knowlesi, a malaria parasite of Southeast Asian macaques, infects humans and can cause fatal malaria. It is difficult to diagnose by microscopy because of morphological similarity to Plasmodium malariae. Nested PCR assay is the most accurate method to distinguish P. knowlesi from other Plasmodium species but is not cost effective in resource-poor settings. Rapid diagnostic tests (RDTs) are recommended for settings where malaria is prevalent. In this study, the effectiveness of three RDTs in detecting P. knowlesi from fresh and frozen patient blood samples was evaluated.MethodsForty malaria patients (28 P. knowlesi, ten P. vivax and two P. falciparum) diagnosed by microscopy were recruited in Sarawak, Malaysian Borneo during a 16-month period. Patient blood samples were used to determine parasitaemia by microscopy, confirm the Plasmodium species present by PCR and evaluate three RDTs: OptiMAL-IT, BinaxNOW® Malaria and Paramax-3. The RDTs were also evaluated using frozen blood samples from 41 knowlesi malaria patients.ResultsOptiMAL-IT was the most sensitive RDT, with a sensitivity of 71% (20/28; 95% CI = 54-88%) for fresh and 73% (30/41; 95% CI = 59-87%) for frozen knowlesi samples. However, it yielded predominantly falciparum-positive results due to cross-reactivity of the P. falciparum test reagent with P. knowlesi. BinaxNOW® Malaria correctly detected non-P. falciparum malaria in P. knowlesi samples but was the least sensitive, detecting only 29% (8/28; 95% CI = 12-46%) of fresh and 24% (10/41; 95% CI = 11-37%) of frozen samples. The Paramax-3 RDT tested positive for P. vivax with PCR-confirmed P. knowlesi samples with sensitivities of 40% (10/25; 95% CI = 21-59%) with fresh and 32% (13/41; 95% CI = 17-46%) with frozen samples. All RDTs correctly identified P. falciparum- and P. vivax-positive controls with parasitaemias above 2,000 parasites/μl blood.ConclusionsThe RDTs detected Plasmodium in P. knowlesi-infected blood samples with poor sensitivity and specificity. Patients with P. knowlesi could be misdiagnosed as P. falciparum with OptiMAL-IT, P. vivax with Paramax-3 and more correctly as non-P. vivax/non-P. falciparum with BinaxNOW® Malaria. There is a need for a sensitive and specific RDT for malaria diagnosis in settings where P. knowlesi infections predominate.

Two treatments, one disease: childhood malaria management in Tanga, Tanzania

BackgroundIn the Tanga District of coastal Tanzania, malaria is one of the primary causes of mortality for children under the age of five. While some children are treated with malaria medications in biomedical facilities, as the World Health Organization recommends, others receive home-care or treatment from traditional healers. Recognition of malaria is difficult because symptoms can range from fever with uncomplicated malaria to convulsions with severe malaria. This study explores why caregivers in the Tanga District of Tanzania pursue particular courses of action to deal with malaria in their children.MethodsQualitative data were collected through interviews with three samples: female caregivers of children under five (N = 61), medical practitioners (N = 28), and traditional healers (N = 18) in urban, peri-urban, and rural areas. The female caregiver sample is intentionally stratified to reflect the greater population of the Tanga District in level of education, marital status, gender of household head, religion, and tribal group affiliation. Qualitative data were counted, coded and analysed using NVivo7 software.ResultsResults indicate that a variety of factors influence treatment choice, including socio-cultural beliefs about malaria symptoms, associations with spiritual affliction requiring traditional healing, knowledge of malaria, and fear of certain anti-malaria treatment procedures. Most notably, some caregivers identified convulsions as a spiritual condition, unrelated to malaria. While nearly all caregivers reported attending biomedical facilities to treat children with fever (N = 60/61), many caregivers stated that convulsions are best treated by traditional healers (N = 26/61). Qualitative interviews with medical practitioners and traditional healers confirmed this belief.ConclusionResults offer insight into current trends in malaria management and have implications in healthcare policy, educational campaigns, and the importance of integrating traditional and biomedical approaches.

Palliative Surgery for Advanced Cancer: Identifying Evidence-Based Criteria for Patient Selection: Case Report and Review of Literature.

BACKGROUND Criteria for selecting patients with advanced cancer for palliative surgery (PS) remains poorly defined. Decision making for PS requires realistic treatment goals with well-defined criteria. Here we discuss a 71-year-old Jehovahs Witness with advanced stage renal cell carcinoma (RCC) who presented with profound anemia due to intractable bleeding from gastric metastasis. After repeated attempts with endoscopic and angiographic management, she underwent surgical palliation. Through this case, we developed 10-item evidence-based criteria for selecting patients for PS. OBJECTIVE The study objective was to provide a review of pertinent literature for PS and identify evidence-based criteria for patient selection. These criteria were relevant for selecting this patient with metastatic RCC and may prove beneficial for selecting advanced cancer patients for PS. METHODS A MEDLINE search revealed 175 publications relevant to PS. Among these, 17 articles defining patient selection criteria (PSC) were reviewed. A frequency-based analysis of each criterion was performed. Another search returned 30 cases of RCC gastric metastases from 25 published reports. Outcome analysis was determined by the Kaplan-Meier actuarial method. RESULTS Ten criteria were identified: symptom control, prognosis, preoperative performance status, quality of life (QoL), tumor burden amenable to palliation, procedure-related morbidity and mortality, feasibility of nonsurgical therapies, anticipated hospitalization, requirement for additional palliation, and cost. This patient met all inclusion criteria and underwent a successful gastrectomy. Median survival for patients with RCC gastric metastasis was 20 months. CONCLUSIONS This report illustrates an example of implementation of evidence-based criteria for selecting advanced cancer patients for PS. Validation of these criteria is warranted.

Richter-type Spigelian hernia: A case report and review of the literature

Highlights • Richter-type Spigelian hernia is rare and reported infrequently in the literature.• Clinical diagnosis is challenging.• CT scan is the diagnostic study of choice.• Primary or mesh repair Surgical repair is the definitive treatment.

Incidence and Prognosis of Primary Gastrinomas in the Hepatobiliary Tract

Importance Zollinger-Ellison syndrome (ZES) is a life-threatening disease caused by a malignant tumor that secretes gastrin (gastrinoma). Gastrinomas typically occur in the pancreas or the duodenum. Objective To describe the incidence and prognosis of very unusual gastrinomas originating in the hepatobiliary tract. Design, Setting, and Participants This study included 223 consecutive patients at the National Institutes of Health and Stanford University Hospital who were enrolled in a prospective protocol to treat ZES using proton pump inhibitors to control acid hypersecretion and surgical resection to ameliorate the tumoral process. Data were collected from June 1982 to August 2017. Main Outcomes and Measures Incidence, location, surgical results, and cure rate and overall survival among patients with gastrinomas that originate in the liver or bile ducts. Cure was defined as serum gastrin levels within the reference range, negative results of a secretin test, and no tumor found on imaging. Results Of the 223 patients who underwent surgery to remove gastrinomas, 7 (3.1%) had liver or biliary tract primary tumors, including 5 men and 2 women (mean age at diagnosis, 43 years; range 27-54 years). The mean serum gastrin level was 817 pg/mL (range, 289-2700 pg/mL). Each patient had positive results of a secretin test. None had evidence of multiple endocrine neoplasia 1. Four patients had primary tumors in the liver (1 in segment II, 2 in segment IV, and 1 in segment V); 3, in the bile duct (1 in the right hepatic duct, 1 in the left hepatic duct, and 1 in the common hepatic duct). Surgical resection required 1 right hepatic lobectomy, 1 left lateral segmentectomy, 2 left hepatic lobectomies, 1 central hepatectomy, and 2 bile duct resections. Four patients had nodal metastases, and no patient had distant metastases. No operative deaths occurred, but 3 patients had complications, including bile duct stricture, portal vein stricture, and biliary fistula. Each patient was disease free in the immediate postoperative period, and 3 had recurrences in the liver and portal lymph nodes (at 3, 11, and 15 years). Three patients (43%) remained free of disease at follow-up ranging from 24 months to 26 years. Conclusions and Relevance Primary gastrinomas of the hepatobiliary tract are uncommon (3%), but the hepatobiliary system is the second most frequent extraduodenopancreatic primary location (after the lymph nodes). These tumors can occur outside the gastrinoma triangle and must be specifically considered. Furthermore, their discovery changes the operative approach because aggressive liver or bile duct resection is indicated, with high rates of long-term cure and survival and acceptable rates of complications. In addition, their discovery dictates that lymph nodes in the porta hepatis should be routinely excised because nearly 50% of patients will have lymph node metastases.

Regression of experimental NIS-expressing breast cancer brain metastases in response to radioiodide/gemcitabine dual therapy

Treating breast cancer brain metastases (BCBMs) is challenging. Na+/I− symporter (NIS) expression in BCBMs would permit their selective targeting with radioiodide (131I−). We show impressive enhancement of tumor response by combining131I− with gemcitabine (GEM), a cytotoxic radiosensitizer. Nude mice mammary fat-pad (MFP) tumors and BCBMs were generated with braintropic MDA-MB-231Br cells transduced with bicistronically-linked NIS and firefly luciferase cDNAs. Response was monitored in vivo via bioluminescent imaging and NIS tumor expression.131I−/GEM therapy inhibited MFP tumor growth more effectively than either agent alone. BCBMs were treated with: high or low-dose GEM (58 or 14.5 mg/Kg×4); 131I− (1mCi or 2×0.5 mCi 7 days apart); and 131I−/GEM therapy. By post-injection day (PID) 25, 82-86% of controls and 78-83% of 131I−-treated BCBM grew, whereas 17% low-dose and 36% high-dose GEM regressed. The latter tumors were smaller than the controls with comparable NIS expression (~20% of cells). High and low-dose 131I−/GEM combinations caused 89% and 57% tumor regression, respectively. High-dose GEM/131I− delayed tumor growth: tumors increased 5-fold in size by PID45 (controls by PID18). Although fewer than 25% of cells expressed NIS, GEM/131I− caused dramatic tumor regression in NIS-transduced BCBMs. This effect was synergistic, and supports the hypothesis that GEM radiosensitizes cells to 131I−.

Pancreatic mucinous cystic neoplasm in a transgender patient.

BackgroundCystic pancreatic lesions are increasingly more frequent detected clinical entities. Mucinous cystic neoplasm (MCN) is a hormone-related pancreatic tumor (HRTP) with a strong predominance in young and middle-aged females.Case presentationHere, we present the case of a 31-year-old surgically transgendered female-to-male patient with a history of alcoholic pancreatitis, on chronic testosterone therapy. He was found to have a pancreatic MCN and underwent distal pancreatectomy and splenectomy.ConclusionTo our knowledge, this is the first reported case of a transgender patient with a history of hormone replacement therapy (HRT) and pancreatic MCN. We consider possible mechanisms for the pathogenesis to explain this patient’s neoplasm.

Author Correction: Genetic dissection of clonal lineage relationships with hydroxytamoxifen liposomes

In the original version of this Article, the authors inadvertently omitted Elizabeth A. Brett, who contributed to the generation of the histology figures, from the author list.This has now been corrected in both the PDF and HTML versions of the Article.

Axillary reverse mapping with indocyanine green or isosulfan blue demonstrate similar crossover rates to radiotracer identified sentinel nodes

Sentinel lymph node (SLN) resection is imperative for breast cancer staging. Axillary reverse mapping (ARM) can preserve arm draining nodes and lymphatics during surgery. ARM is generally performed with isosulfan blue (ISB), restricting its use for concurrent SLN biopsy. Indocyanine green (ICG) could serve as an alternative to ISB for ARM procedures.

The evolving relationship of wound healing and tumor stroma

The stroma in solid tumors contains a variety of cellular phenotypes and signaling pathways associated with wound healing, leading to the concept that a tumor behaves as a wound that does not heal. Similarities between tumors and healing wounds include fibroblast recruitment and activation, extracellular matrix (ECM) component deposition, infiltration of immune cells, neovascularization, and cellular lineage plasticity. However, unlike a wound that heals, the edges of a tumor are constantly expanding. Cell migration occurs both inward and outward as the tumor proliferates and invades adjacent tissues, often disregarding organ boundaries. The focus of our review is cancer associated fibroblast (CAF) cellular heterogeneity and plasticity and the acellular matrix components that accompany these cells. We explore how similarities and differences between healing wounds and tumor stroma continue to evolve as research progresses, shedding light on possible therapeutic targets that can result in innovative stromal-based treatments for cancer.