Diagnosis of severe respiratory infections in immunocompromised patients

Abstract

An increasing number of critically ill patients are immunocompromised. Acute hypoxemic respiratory failure (ARF), chiefly due to pulmonary infection, is the leading reason for ICU admission. Identifying the cause of ARF increases the chances of survival, but may be extremely challenging, as the underlying disease, treatments, and infection combine to create complex clinical pictures. In addition, there may be more than one infectious agent, and the pulmonary manifestations may be related to both infectious and non-infectious insults. Clinically or microbiologically documented bacterial pneumonia accounts for one-third of cases of ARF in immunocompromised patients. Early antibiotic therapy is recommended but decreases the chances of identifying the causative organism(s) to about 50%. Viruses are the second most common cause of severe respiratory infections. Positive tests for a virus in respiratory samples do not necessarily indicate a role for the virus in the current acute illness. Invasive fungal infections (Aspergillus, Mucorales, and Pneumocystis jirovecii) account for about 15% of severe respiratory infections, whereas parasites rarely cause severe acute infections in immunocompromised patients. This review focuses on the diagnosis of severe respiratory infections in immunocompromised patients. Special attention is given to newly validated diagnostic tests designed to be used on non-invasive samples or bronchoalveolar lavage fluid and capable of increasing the likelihood of an early etiological diagnosis.

The microbial coinfection in COVID-19

“…However, little attention was paid to the bacterial and fungal coinfection of this disease, and the standardized testing process of coinfection is still unavailable. It is difficult to distinguish bacterial or fungal infections from existing viral pneumonia based on clinical and radiological performance (Azoulay et al 2020 ). In addition, there are articles indicating that calcitonin may also be an auxiliary means for detecting whether there is bacterial or fungal coinfection (Wiegers et al 2019 ) as the concentration of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and IL-6 increases, which results in the massive production and release of parathyroid-derived calcitonin during bacterial infection.…”

Temporal trends of outcomes of neutropenic patients with ARDS enrolled in therapeutic clinical trials

“…Although limited by a highly selected (e.g., exclusion of stem cell transplant subjects) and relatively small number of neutropenic patients as well as by consideration of center-dependent outcomes (ventilator-free and ICU-free days), our findings are important. We show that the prognosis of these patients has improved over time even in prospective randomized controlled studies, whereas this trend has previously been observed only in retrospective observational studies [1,6].…”

Hämatoonkologie und Intensivmedizin

“…Vor allem bei blutungsgefährdeten Patienten könnte die Kryobiopsie eine zukünftige Option darstellen [18,21]. Ein rezenter Review des Nine-i-Netzwerks liefert weitere Ausführungen zum differenzierten diagnostischen Vorgehen bei schweren respiratorischen Infekten des immunsupprimierten Patienten [29].…”