Laboratory preparation and evaluation of a multiparameter hemocytometry control

A protocol for the laboratory preparation of a multiparameter hemocytometry control is given. Human platelets, stabilized by a basically simplified and inexpensive fixation procedure, are added to our previously described white and red blood cell control. Evaluation of this multiparameter control shows good precision characteristics and acceptable mechanical stability for at least 7 weeks, as measured in the Coulter counter Model S Plus-II. The control can basically contribute to the realization of the essence of internal quality control: continuous self-auditing and continuous attempts at improvement of performance.     

Gametocytogenesis and ribosomal rRNA gene organisation in the rodent malarias Plasmodium chabaudi and Plasmodium berghei

A cloned Plasmodium berghei (ANKA) isolate was syringe passaged repeatedly to generate a line that was non-infective to Anopheles stephensi. Ribosomal gene organisation of this non-infective line was then compared to its infective ancestor. DNA was also prepared from asexual parasites and gametocytes of P. chabaudi and the arrangement of the rRNA genes of this species was studied. Although macrogametocytes have many more ribosomes than microgametocytes, this increase does not appear to stem from an amplification of the rRNA genes, as no differences either in the quantity or the arrangement of the rDNA could be detected. Furthermore, the loss of infectivity of the P. berghei gametocytes does not seem to be due to a reduction or rearrangement of sequences coding for the rRNA genes. P. chabaudi and P. berghei DNA failed to show any homology to a repetitive DNA sequence cloned from P. falciparum. We conclude that this probe, PFH8rep20, is specific for P. falciparum.     

Characteristics of bacterial infections and prevalence of multidrug-resistant bacteria in hospitalized patients with liver cirrhosis in Germany

Introduction and ObjectivesBacterial infections are associated with a dismal prognosis in patients with liver cirrhosis. Data on their prevalence and the associated pathogen spectra in Germany are scarce. This study aimed to evaluate the impact of bacterial infections on mortality in hospitalized patients with liver cirrhosis and to analyze the prevalence of multidrug-resistant (MDR) bacteria in a German tertiary care center.Patients and MethodsConsecutive, non-electively hospitalized patients with liver cirrhosis were enrolled in this study between 03/2019-06/2021. All patients underwent clinical, laboratory and microbiological testing to detect potential bacterial infections. Patients were followed for 30 days regarding the composite endpoint of death or liver transplantation (mortality).ResultsIn total, 239 patients were recruited (median MELD 18). Bacterial infection was detected in 81 patients (33.9%) at study inclusion. A total of 70 patients (29.3%) developed a hospital-acquired infection. When comparing community-acquired and hospital-acquired infections, the pathogen pattern shifted from a gram-negative to a more gram-positive spectrum and showed an increase of Staphylococcus spp.. MDR bacteria were detected in seven infected patients (5.8%). 34 patients reached the composite endpoint during 30-days follow-up. In multivariable logistic regression analysis, the presence of infection during hospitalization remained independently associated with higher mortality (OR 2.522, 95% CI 1.044 - 6.091, p = 0.040).ConclusionsThis study demonstrates that bacterial infections are common in hospitalized patients with liver cirrhosis in Germany and are a major determinant of short-term mortality. Our data highlight the importance of regional differences in MDR bacteria and may guide physicians' decision-making regarding calculated antibiotic treatment.