Search

Background Artemisinin-based combination therapy (ACT) for the treatment of malaria is highly effective, well tolerated and safe. Episodes of delayed haemolysis occur in up to 57.9% of patients with severe malaria treated with intravenous artesunate, mainly caused by ‘pitting’ of infected red blood cells in the spleen and the delayed loss of these once-infected RBCs (oiRBCs). Several reports indicate that post-treatment haemolysis (PTH) also occurs in uncomplicated malaria treated with oral ACT, calling for systematic investigation. Methods A prospective observational study to identify the incidence of PTH after oral ACT, defined as increased lactate dehydrogenase activity and low haptoglobin level on Day 14 after treatment. Patients were enrolled at two study centres in Germany and Italy. Study visits took place on Days 1, 3, 7, 14 and 28. Laboratory investigations included extended clinical routine laboratory tests, quantitative PfHRP2, anti-RBC antibodies and oiRBCs. The state of semi-immunity to malaria was assessed from childhood and ongoing exposure to Plasmodium spp. as per patient history. Results A total of 134 patients with uncomplicated malaria and 3-day ACT treatment were recruited. Thirty-seven (37.4%) of 99 evaluable patients with Pf and none of 9 patients with non-Pf malaria exhibited PTH on d14. Patients with PTH had higher initial parasitaemia, higher oiRBC counts on d3 and a 10-fold decrease in oiRBCs between d7 and d14 compared with patients without PTH. In patients with PTH, loss of haemoglobin was 4-fold greater in non-Africans than in Africans (−1.3 vs −0.3 g/dl). Semi-immune African patients with PTH showed markedly increased erythropoiesis on d14 compared with not semi-immune African and non-African patients with PTH. Conclusions PTH is common in patients with uncomplicated malaria and oral ACT. While the observed loss of haemoglobin will often not be clinically relevant, it could aggravate pre-existing anaemia, warranting follow-up examinations in populations at risk.

BACKGROUND: Panton-Valentine leukocidin (PVL)–producing Staphylococcus aureus (PVL-SA) strains are frequently associated with large, recurring abscesses in otherwise healthy young individuals. The typical clinical presentation and the recommended diagnostic evaluation and treatment are not widely known. METHODS: This review is based on pertinent publications retrieved by a selective search in PubMed, with special attention to international recommendations. RESULTS: PVL-SA can cause leukocytolysis and dermatonecrosis through specific cell-wall pore formation. Unlike other types of pyoderma, such conditions caused by PVL-SA have no particular site of predilection. In Germany, the PVL gene can be detected in 61.3% (252/411) of skin and soft tissue infections with S. aureus. Skin and soft tissue infections with PVL-SA recur three times as frequently as those due to PVL-negative S. aureus. They are diagnosed by S. aureus culture from wound swabs and combined nasal/pharyngeal swabs, along with PCR for gene detection. The acute treatment of the skin abscesses consists of drainage, followed by antimicrobial therapy if needed. Important secondary preventive measures include topical cleansing with mupirocin nasal ointment and whole-body washing with chlorhexidine or octenidine. The limited evidence (level IIb) concerning PVL-SA is mainly derived from nonrandomized cohort studies and experimental analyses. CONCLUSION: PVL-SA skin infections are easily distinguished from other skin diseases with targeted history-taking and diagnostic evaluation.

Background The microbial etiology of prosthetic valve infective endocarditis (PVE) can be difficult to identify. Our aim was to investigate the benefit of molecular imaging technique fluorescence in situ hybridization (FISH) combined with 16S rRNA-gene polymerase chain reaction (PCR) and sequencing (FISHseq) for the analysis of infected prosthetic heart valves. Methods We retrospectively evaluated the diagnostic outcome of 113 prosthetic valves from 105 patients with suspected PVE, treated in 2003–2013 in the Department of Cardiac Surgery, Charité University Medicine Berlin. Each prosthetic valve underwent cultural diagnostics and was routinely examined by FISH combined with 16S rRNA gene PCR and sequencing. We compared classical microbiological culture outcomes (blood and valve cultures) with FISHseq results and evaluated the diagnostic impact of the molecular imaging technique. Results Conventional microbiological diagnostic alone turned out to be insufficient, as 67% of preoperative blood cultures were noninformative (negative, inconclusive, or not obtained) and 67% of valve cultures remained negative. FISHseq improved the conventional cultural diagnostic methods in PVE in 30% of the cases and increased diagnostic accuracy. Of the valve culture–negative PVE cases, FISHseq succeeded in identifying the causative pathogen in 35%. Conclusions FISHseq improves PVE diagnostics, complementing conventional cultural methods. In addition to species identification, FISH provides information about the severity of PVE and state of the pathogens (eg, stage of biofilm formation, activity, and localization on and within the prosthetic material). As a molecular imaging technique, FISHseq enables the unambiguous discrimination of skin flora as contaminant or infectious agent.

Purpose To investigate antimicrobial use and primary and nosocomial infections in hospitalized COVID-19 patients to provide data for guidance of antimicrobial therapy. Methods Prospective observational cohort study conducted at Charité–Universitätsmedizin Berlin, including patients hospitalized with SARS-CoV-2-infection between March and November 2020. Results 309 patients were included, 231 directly admitted and 78 transferred from other centres. Antimicrobial therapy was initiated in 62/231 (26.8%) of directly admitted and in 44/78 (56.4%) of transferred patients. The rate of microbiologically confirmed primary co-infections was 4.8% (11/231). Although elevated in most COVID-19 patients, C-reactive protein and procalcitonin levels were higher in patients with primary co-infections than in those without (median CRP 110 mg/l, IQR 51–222 vs. 36, IQR 11–101, respectively; p Conclusions Primary co-infections are rare, yet antimicrobial use was frequent, mostly based on clinical worsening and elevated inflammation markers without clear evidence for co-infection. More reliable diagnostic prospects may help to reduce overtreatment. Rates of nosocomial infections are substantial in severely ill patients on organ support and associated with worse patient outcome.

COVID-19 is highly variable in its clinical presentation, ranging from asymptomatic infection to severe organ damage and death. We characterized the time-dependent progression of the disease in 139 COVID-19 inpatients by measuring 86 accredited diagnostic parameters, such as blood cell counts and enzyme activities, as well as untargeted plasma proteomes at 687 sampling points. We report an initial spike in a systemic inflammatory response, which is gradually alleviated and followed by a protein signature indicative of tissue repair, metabolic reconstitution, and immunomodulation. We identify prognostic marker signatures for devising risk-adapted treatment strategies and use machine learning to classify therapeutic needs. We show that the machine learning models based on the proteome are transferable to an independent cohort. Our study presents a map linking routinely used clinical diagnostic parameters to plasma proteomes and their dynamics in an infectious disease., Graphical abstract, Demichev, Tober-Lau et al., present a time-resolved molecular map of the COVID-19, measuring plasma proteomes of patients with COVID-19 along with an extensive panel of clinical diagnostic parameters at 687-time points. They describe the specificity and dynamics, as well as the predictive and prognostic power of the molecular signatures in COVID-19.

Objectives Dexamethasone has become the standard of care for severe coronavirus disease 2019 (COVID-19), but its virological impact is poorly understood. The objectives of this work were to characterize the kinetics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) concentration in the upper respiratory tract (URT) and the antibody response in patients with (D+) and without (D–) dexamethasone treatment. Methods Data and biosamples from hospitalized patients with severe COVID-19, enrolled between 4th March and 11th December 2020 in a prospective observational study, were analysed. SARS-CoV-2 virus concentration in serial URT samples was measured using RT-PCR. SARS-CoV-2-specific immunoglobulins A and G (IgA and IgG) were measured in serum samples using S1-ELISA. Results We compared 101 immunocompetent patients who received dexamethasone (according to the inclusion criteria and dosage determined in the RECOVERY trial) to 93 immunocompetent patients with comparable disease severity from the first months of the pandemic, who had not been treated with dexamethasone or other glucocorticoids. We found no inter-group differences in virus concentration kinetics, duration of presence of viral loads >106 viral copies/mL (D+ median 17 days (IQR 13–24), D– 19 days (IQR 13–29)), or time from symptom onset until seroconversion (IgA: D+ median 11.5 days (IQR 11–12), D– 14 days (IQR 11.5–15.75); IgG: D+ 13 days (IQR 12–14.5), D– 12 days (IQR 11–15)). Conclusion Dexamethasone does not appear to lead to a change in virus clearance or a delay in antibody response in immunocompetent patients hospitalized with severe COVID-19.