Transfusion-transmitted Babesia spp.: a changing landscape of epidemiology, regulation, and risk mitigation.

Babesia spp. are tick-borne parasites with a global distribution and diversity of vertebrate hosts. Over the next several decades, climate change is expected to impact humans, vectors, and vertebrate hosts and change the epidemiology of Babesia. Although humans are dead-end hosts for tick-transmitted Babesia, human-to-human transmission of Babesia spp. from transfusion of red blood cells and whole blood-derived platelet concentrates has been reported. In most patients, transfusion-transmitted Babesia (TTB) results in a moderate-to-severe illness. Currently, in North America, most cases of TTB have been described in the United States. TTB cases outside North America are rare, but case numbers may change over time with increased recognition of babesiosis and as the epidemiology of Babesia is impacted by climate change. Therefore, TTB is a concern of microbiologists working in blood operator settings, as well as in clinical settings where transfusion occurs. Microbiologists play an important role in deploying blood donor screening assays in Babesia endemic regions, identifying changing risks for Babesia in non-endemic areas, investigating recipients of blood products for TTB, and drafting TTB policies and guidelines. In this review, we provide an overview of the clinical presentation and epidemiology of TTB. We identify approaches and technologies to reduce the risk of collecting blood products from Babesia-infected donors and describe how investigations of TTB are undertaken. We also describe how microbiologists in Babesia non-endemic regions can assess for changing risks of TTB and decide when to focus on laboratory-test-based approaches or pathogen reduction to reduce TTB risk.

USE of CLINICAL TEST CLUSTERS VERSUS ADVANCED IMAGING STUDIES in the MANAGEMENT of PATIENTS with a SUSPECTED SLAP TEAR.

BACKGROUND AND PURPOSE: The Magnetic Resonance Arthrogram (MRA) has served as the gold standard for identifying patients with possible Superior Labrum Anterior-Posterior (SLAP) lesions and are often required by orthopaedic surgeons prior to clinical evaluation. However, as the literature shows MRA sensitivity as 0.65-0.98, and specificity between 0.80-1.00, there is still room for misinterpretation of the imaging study, and potential mismanagement of a patient who may or may not exhibit a true SLAP lesion. It is proposed that by grouping a series of clinical special tests it may be possible to develop greater sensitivity in identifying a SLAP lesion, resulting in the ability to better manage this patient population, thus avoiding unnecessary and costly imaging studies and decreased referrals to surgical specialists. The purpose of this study is to examine specific combinations of SLAP lesion special tests and identify which clusters of tests have the highest sensitivity and specificities. This may allow therapists to improve the management of their patients by reliably diagnosing a SLAP lesion and referring only those who may need surgery to a physician. STUDY DESIGN: Literature review, diagnostic sensitivity/specificity outcomes. METHODS: A retrospective search of the current peer-reviewed literature was performed in an effort to identify the clinical special tests with the greatest sensitivity and specificity in identifying SLAP lesions. Based upon that search, the study was limited to five special tests: Biceps Load I, Biceps Load II, Speed's, Passive Compression, and O'Brien's tests. A multiple regression analysis was performed that looked at grouping of the tests to determine the diagnostic sensitivity/specificity when grouped. RESULTS: Obtaining positive results on three of the five special tests resulted in a sensitivity of 0.992-0.999 and a specificity of 0.992-0.999. The combination of the Biceps Load I/II and O'Brien's showed the highest sensitivity and specificity. CONCLUSION: The results indicate that a combination of at least three positive SLAP lesion tests may be clinically useful in diagnosing a shoulder SLAP lesion with greater diagnostic accuracy than those reported for MRI/MRA, thus improving patient management by referring only those who may require surgical intervention to a physician. LEVEL OF EVIDENCE: 2c, "Outcomes" Research.