Single-stage group testing uses compressed sensing for efficient high-throughput SARS-CoV-2 testing.

Carbapenem-resistant Acinetobacter baumannii (CRAB) causes colonization and infection predominantly in hospitalized patients. Distinction between the two is a challenge. When CRAB is isolated from a non-sterile site (soft tissue, respiratory samples, etc.), it probably represents colonization unless clear signs of infection (fever, elevated white blood count, elevated inflammatory markers and abnormal imaging) are present. Treatment is warranted only for true infections. In normally sterile sites (blood, cerebrospinal fluid) the presence of indwelling medical devices (catheters, stents) should be considered when evaluating positive cultures. In the absence of such devices, the isolate represents an infection and should be treated. If an indwelling device is present and there are no signs of active infection, the device should be replaced if possible, and no treatment is required. If there are signs of an active infection the device should be removed or replaced, and treatment should be administered. Current treatments options and clinical data are limited. No agent or combination regimen has been shown to be superior to any other in randomized clinical trials. Ampicillin-sulbactam appears to have the best evidence for initial use. This is probably due to its ability to saturate penicillin-binding proteins 1 and 3 when given in high dose. Tigecycline when used should be given in high dose as well. Polymyxins are a treatment option but are difficult to dose correctly and have significant side effects. Newer treatment options such as eravacycline and cefiderocol have potential; however, currently there are not enough data to support their use as single agents. Combination therapy appears to be the best treatment option and should always include high-dose ampicillin-sulbactam combined with another active agent such as high-dose tigecycline, polymyxins, etc. These infections require a high complexity of skill, and an infectious disease specialist should be involved in the management of these patients.

Neutropenic enterocolitis (NEC) is a life-threatening disease with substantial morbidity and mortality, seen primarily in patients with hematologic malignancies. The frequency of NEC has increased with the widespread use of chemotherapeutic agents such as the taxanes, which cause severe gastrointestinal mucositis. Neutropenic patients with fever and abdominal symptoms (cramping, pain, distention, diarrhea, GI bleeding), should undergo evaluation of the abdomen for bowel wall thickening of >4 mm, the hallmark of NEC. Clostridium difficile infection should be ruled out, as well as other etiologies such as graft-versus-host disease. Complications include bacteremia, which is often polymicrobial, hemorrhage, and bowel wall perforation/abscess formation. Management includes bowel rest, correction of cytopathies and coagulopathies, and broad spectrum antibiotics and antifungal agents. Surgical intervention may be necessary to manage complications such as hemorrhage and perforation and should be delayed, if possible, until recovery from neutropenia.

Key Points: An immunodeficiency scoring index for RSV-infected hematopoietic cell transplant recipients predicts the risk of pneumonia and death. This scoring index would assist in the decision-making for initiating antiviral therapy in patients at high risk for poor outcomes.