Jundishapur Journal of Microbiology
Volume:15 Issue: 11, Nov 2022

Staphylococcus aureus can cause fatal pneumonia. The evolution of bacteria and the overuse of antibiotics have enhanced the drug resistance of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive Staphylococcus aureus (MSSA).

This study aimed to recapitulate the microbiological profile and clinical characteristics of paediatric patients with MRSA.

This retrospective study was conducted to investigate 1372 paediatric patients with S. aureus pneumonia from January 2017 to December 2021. Sputum specimens were collected and processed for performing bacterial culture and drug sensitivity tests. Medical records of patients were reviewed for clinical characteristics and laboratory examination results.

The MRSA and MSSA pneumonia mainly occurred in infants; however, comparisons of sex, age, and sampling time between patients with MRSA and MSSA pneumonia showed no significant differences (P > 0.05). The results of drug sensitivity in sputum culture revealed that all MRSA and MSSA isolates were susceptible to vancomycin, tigecycline, linezolid, teicoplanin, and ceftaroline. Methicillin-sensitive Staphylococcus aureus was completely sensitive to rifampicin and oxacillin. Methicillin-resistant Staphylococcus aureus was completely resistant to penicillin and oxacillin, while MSSA was less sensitive to penicillin. Methicillin-resistant Staphylococcus aureus and MSSA both maintained high sensitivity rates to gentamicin, sulfamethoxazole-trimethoprim, levofloxacin, and moxifloxacin, with the exception of clindamycin and erythromycin. According to our results, moreover, the sensitivity of MRSA to gentamicin and sulfamethoxazole-trimethoprim was significantly higher than that of MSSA (P < 0.05). The common symptoms of patients with S. aureus pneumonia were fever, cough, and wheezing. patients with MRSA pneumonia had significantly higher counts of white blood cells (WBCs), C-reactive protein (CRP), and procalcitonin (PCT) than patients with MSSA pneumonia (P < 0.05).

The results of antimicrobial sensitivity test in sputum culture of MRSA and MSSA isolates can reflect the sensitivity of antibiotics and guide the use of clinical antibiotics. Infectious biomarkers can reflect the severity of infection and guide prognosis.

 Candida infections are a significant cause of morbidity and mortality in hospitalized patients. Acquired resistance to antifungal agents and strains with intrinsic resistance makes it hard to manage the infection.

 We aimed to examine the risk factors of candidemia associated with patient mortality, the species causing candidemia, and their antifungal susceptibility.

 Patient data were collected from medical records retrospectively. MALDI-TOF MS was used to identify Candida species. Antifungal susceptibility testing was conducted by the colorimetric broth microdilution method.

 A total of 155 patients were included in the study. The incidences of candidemia were 0.92, 0.72, 0.99, 0.97, and 2.28 per 1,000 cases in 2016, 2017, 2018, 2019, and 2020, respectively. Candida albicans accounted for 45% of all cases, followed by C. parapsilosis complex (28%), C. tropicalis (10%), and C. glabrata (8%). The 30-day crude mortality was 45%. There was no significant difference in mortality between C. albicans and non-albicans yeast species. The susceptibility rates for anidulafungin, micafungin, caspofungin, voriconazole, and fluconazole were as follows: 97, 97, 97, 97, and 90% in C. albicans, 95, 95, 98, 72, and 67% in C. parapsilosis complex, and 100, 100, 100, 38, and 63% in C. tropicalis. The susceptibility rates for anidulafungin, micafungin, and caspofungin in C. glabrata were 100, 100, and 92%, respectively. All 12 C. glabrata strains were susceptible-dose-dependent against fluconazole and uninterpretable for voriconazole.

 Incidences of candidemia and susceptibility patterns of strains may vary over time and amongst the regions. Candida albicans was the predominant strain, and echinocandins demonstrated the highest susceptibility rates against the most common species isolated in this study. Antifungal susceptibility tests are crucial in guiding patient treatment.

 SARS-CoV-2 infections (COVID-19) first occurred in Wuhan, China, in December 2019 and spread worldwide, causing significant mortality and morbidity. IL-17A may mediate numerous immunopathological effects secondary to cytokine release syndrome during SARS-CoV-2 infection. However, there has not been enough research on its effect on prognosis.

 This study evaluated the predictive power of serum interleukin (IL)-17A level as a prognostic marker in COVID-19.

 The study included 152 patients diagnosed with COVID-19 by real-time polymerase chain reaction analysis of nasopharyngeal swab samples in the infectious diseases department and intensive care unit of our hospital between October 1 and December 31, 2020. The control group consisted of 40 asymptomatic healthcare workers who had negative RT-PCR results during routine COVID-19 screening in our hospital. Samples were collected in anticoagulant-free tubes and left at room temperature for 30 minutes. Afterward, it was centrifuged at 1000 × g for 15 minutes at 4°C per the instructions provided with the enzyme-linked immunoassay (ELISA) kit. Serum IL-17A levels were measured using the Human Interleukin 17A ELISA Kit.

 Serum IL-17A levels were significantly higher in COVID-19 patients than in controls (P < 0.001). IL-17A levels increased significantly in association with disease severity in patients with the moderate, severe, and critical disease, with a less pronounced difference between severe and critical patients (moderate vs. severe, P < 0.001; severe vs. critical, P = 0.048). IL-17A levels at hospital admission and day 7 were significantly higher in non-surviving patients (P < 0.001). At a cut-off value of 210.25 ng/L, IL-17A at admission had a predictive power of 0.792 (P < 0.001). Compared to baseline, IL-17A values on day seven were significantly increased in non-survivors (P = 0.004) and decreased in survivors (P = 0.014). An increase of 26.17 ng/L or more on day 7 had a predictive mortality power of 0.634 (P = 0.005).

 The results of this study suggest that IL-17A, an important part of the immune system previously shown to be useful in the treatment and follow-up of COVID-19, may also help predict mortality in COVID-19 patients.

 Multidrug-resistant (MDR) Acinetobacter baumannii is one of the most common nosocomial pathogens. Antimicrobial peptides (AMPs) have been introduced as a viable alternative to antibiotics in the treatment of MDR pathogens.

 This study was designed to assess the in vitro pharmacokinetics of the combination of two potent AMPs, LL-37 and oncorhyncin II, against A. baumannii (ATCC19606).

 The synthesized genes of oncorhyncin II and LL-37 were introduced into Escherichia coli BL21 as the expression host. The minimum inhibitory concentration (MIC), time-kills, and growth kinetics of these peptides were used to evaluate their antimicrobial efficiencies against A. baumannii (ATCC19606).

 LL-37 and oncorhyncin II recombinant peptides showed MIC of 30.6 and 95.87 µg/mL against A. baumannii, respectively. Additive action was confirmed by combining the generated AMPs at the checkerboard approach. The combination of LL-37 and oncorhyncin II at 2 × MIC resulted in a rapid drop in log10 CFU/mL of A. baumannii in the time-kill and growth kinetic findings studies.

 The combination of the produced LL-37 and oncorhyncin II synergizes the bioactivity of the individual peptides. Therefore, these peptides or their combinations might function as novel antibiotics and be used to develop and produce new antimicrobial drugs for the treatment of infections caused by A. baumannii.

 The outbreak of a new coronavirus in China in 2019 (COVID-19) caused a global health crisis.

 This study was performed to investigate the effect of different underlying diseases on mortality in patients with COVID-19.

 This retrospective cohort study was performed on COVID-19 patients admitted to the Shahid Rahimi and Sohada-ye Ashayer teaching hospitals in Khorramabad, Iran, from 2019 to 2021. Data on disease severity, clinical manifestations, mortality, and underlying disorders were collected and analyzed using the SPSS software version 22 at a 95% confidence interval and 0.05 significance level.

 The study included 9653 men (48%) and 10332 women (52%). Patients with chronic kidney diseases, cancer, chronic obstructive pulmonary disease, hypertension, cardiovascular disease, and diabetes were at higher mortality risk than those without these underlying diseases, respectively. However, there was no significant relationship between asthma and mortality. Also, age > 50 years, male gender, oxygen saturation < 93 on admission, and symptoms lasting ≤ 5 days were associated with increased mortality.

 Since patients with underlying diseases are at higher mortality risk, they should precisely follow the advice provided by health authorities and receive a complete COVID-19 vaccination series.

 Polymyositis is an idiopathic inflammatory myopathy that mainly manifests itself with muscle weakness. Patients with polymyositis have a higher risk of developing infections and malignancies. We report concurrent pulmonary and cerebral lesions in a polymyositis patient with many diagnostic challenges.

 A 56-year-old woman complained of a productive cough and dyspnea from two weeks ago. Her symptoms gradually progressed until a sudden loss of consciousness occurred. She was a known case of polymyositis and was treated with oral prednisolone. Imaging revealed concurrent pulmonary and cerebral lesions. Initially, the patient underwent empirical therapy. However, the patient underwent a bronchoscopy because she did not respond to treatment. Specimens obtained from respiratory secretions revealed branched septate hyphae, and the culture was positive for Aspergillus fumigatus. She was diagnosed with invasive aspergillosis, so we replaced the therapy with voriconazole. After three months, the lung lesions improved, but the number and extent of cerebral lesions increased. Finally, after a stereotactic biopsy, the patient was diagnosed with astrocytoma and became a candidate for radiotherapy.

 Patients with polymyositis are prone to contracting opportunistic infections and malignancies. Both of them can mimic each other and present diagnostic challenges to physicians. Thus, they should think about them for early diagnosis and timely treatment.