Methicillin-resistant Staphylococcus aureus Pyomyositis inducing Guillain-Barré Syndrome - A rare and unexpected clinical presentation

Tropical pyomyositis is characterized by deep suppurative skeletal muscle infection most commonly by Staphylococcal Aureus (S. aureus) with increasing incidence of infection by community acquired methicillin resistant S. aureus(CA-MRSA). The initial clinical presentation is generally non-specific and requires a high index of suspicion. We report the clinical course of a child from subtropical area of North India who developed multiple deep pyogenous collections, complicated with CA-MRSA septicaemia and followed by unusual complications consistent with Guillain-Barré Syndrome.

The impact of infectious diseases consultation on the management and outcomes of Pseudomonas aeruginosa bacteraemia in adults: a retrospective cohort study

Background Pseudomonas aeruginosa bacteraemia (PAB) is associated with high mortality. The benefits of infectious diseases consultation (IDC) has been demonstrated in Staphylococcal aureus bacteraemia and other complex infections. Impact of IDC in PAB is unclear. This study aimed to evaluate the impact of IDC on the management and outcomes in patients with PAB. Methods This is a retrospective cohort single-centre study from 1 November 2006 to 29 May 2019, in all adult patients admitted with first episode of PAB. Data collected included demographics, clinical management and outcomes for PAB and whether IDC occurred. In addition, 29 Pseudomonas aeruginosa (PA) stored isolates were available for Illumina whole genome sequencing to investigate if pathogen factors contributed to the mortality. Results A total of 128 cases of PAB were identified, 71% received IDC. Patients who received IDC were less likely to receive inappropriate duration of antibiotic therapy (4.4%; vs 67.6%; p < 0.01), more likely to be de-escalated to oral antibiotic in a timely manner (87.9% vs 40.5%; p < 0.01), undergo removal of infected catheter (27.5% vs 13.5%; p = 0.049) and undergo surgical intervention (20.9% vs 5.4%, p = 0.023) for source control. The overall 30-day all-cause mortality rate was 24.2% and was significantly higher in the no IDC group in both unadjusted (56.8% vs 11.0%, odds ratio [OR] = 10.63, p < 0.001) and adjusted analysis (adjusted OR = 7.84; 95% confidence interval, 2.95–20.86). The genotypic analysis did not reveal any PA genetic features associated with increased mortality between IDC versus no IDC groups. Conclusion Patients who received IDC for PAB had lower 30-day mortality, better source control and management was more compliant with guidelines. Further prospective studies are necessary to determine if these results can be validated in other settings.

Lipoproteins Are Responsible for the Pro-Inflammatory Property of Staphylococcus aureus Extracellular Vesicles

Staphylococcal aureus (S. aureus), a Gram-positive bacteria, is known to cause various infections. Extracellular vesicles (EVs) are a heterogeneous array of membranous structures secreted by cells from all three domains of life, i.e., eukaryotes, bacteria, and archaea. Bacterial EVs are implied to be involved in both bacteria–bacteria and bacteria–host interactions during infections. It is still unclear how S. aureus EVs interact with host cells and induce inflammatory responses. In this study, EVs were isolated from S. aureus and mutant strains deficient in either prelipoprotein lipidation (Δlgt) or major surface proteins (ΔsrtAB). Their immunostimulatory capacities were assessed both in vitro and in vivo. We found that S. aureus EVs induced pro-inflammatory responses both in vitro and in vivo. However, this activity was dependent on lipidated lipoproteins (Lpp), since EVs isolated from the Δlgt showed no stimulation. On the other hand, EVs isolated from the ΔsrtAB mutant showed full immune stimulation, indicating the cell wall anchoring of surface proteins did not play a role in immune stimulation. The immune stimulation of S. aureus EVs was mediated mainly by monocytes/macrophages and was TLR2 dependent. In this study, we demonstrated that not only free Lpp but also EV-imbedded Lpp had high pro-inflammatory activity.

Nasopharyngeal Carriage of Staphylococcus aureus among Horses and Horse Handlers in Kano Metropolis, Nigeria

Staphylococcal species are important opportunistic bacterial pathogens that can asymptomatically colonize both human and animals bodies. The presence of nasopharyngeal carriage Staphylococci has been an increased risk factor of acquiring an infection with this pathogen. The present study aimed at determining the nasopharyngeal carriage of Staphylococcal aureus in horses and horse handlers in Kano metropolis, Nigeria. One hundred and sixty (160) non-duplicated nasopharyngeal samples were collected using sterile swab stick from each horse and 100 from consented horse handlers. All the samples were analyzed using a standard bacteriological procedure. Antibiotics susceptibility testing to eight (8) most commonly used antibiotics was carried out using a modified Kirby Bauer method. One hundred and forty-two (88.8%) staphylococcal isolates were recovered from horses and 84 (84.0%) from horse handlers. Among all the isolated staphylococci high sensitivity was observed in response to Gentamycin and Ciprofloxacin antibiotics, while Tetracycline was found to have the least activity. The report of this study showed a high prevalence of Staphylococci among horses and horse handlers. Moreover, it confirmed the tendency of Staphylococcal isolates cross-transmission between horses and handlers in the study site. This study indicated the importance of increase in handler's awareness of possible risk factors of staphylococcal colonization that can lead to invasive infection. Keywords: Antibiotics, Horses, Horse Handlers, Nasopharyngeal, Staphylococci

Nafcillin-Associated Hypokalemia

Hypokalemia is a common finding in various clinical settings; it is associated with diuretic use and loss of potassium via the gastrointestinal tract. Less common causes are renal tubular acidosis, diabetic ketoacidosis, excess insulin, primary hyperaldosteronism, and medications, such as amphotericin B. Nafcillin, a narrow-spectrum penicillin class antibiotic, which is selectively prescribed for methicillin-susceptible Staphylococcal aureus infections, and is commonly associated with gastrointestinal side effects, such as nausea, vomiting, and abdominal pain. However, in rare cases it can cause hypokalemia, which is usually overlooked. Severe hypokalemia was detected in a 59-year-old male patient hospitalized due to traumatic cerebral hemorrhage who received 12 g of nafcillin per day for more than 2 weeks for sepsis caused by methicillin-sensitive <i>Staphylococcus epidermidis</i>. We confirmed the association between nafcillin and hypokalemia through further evaluation and a review of the relevant literature. Clinicians should be aware of hypokalemia as a complication when using high doses of nafcillin.

Clinical Profile of Foot Gangrene and Its Outcome in a Rural Medical College

BACKGROUND Gangrene refers to the dead or dying body tissue (s) that occurs because the local blood supply to the tissue is either lost or is inadequate to keep the tissue alive. Foot gangrene is becoming a major concern which changes the quality of life, and also the social and economic point of view. We wanted to study the clinical profile of foot gangrene, determine the most common aetiology, distribution of age and sex, presentation, associated risk factors, commonest organisms involved, ways to find and manage the complications, and study the outcomes of foot gangrene in a rural medical college. METHODS Clinical profiles of all 50 patients with foot gangrene were studied as a prospective observational study in a rural medical college from October 2018 to October 2020. All cases were evaluated by history, clinical examination, investigations, management and follow up. RESULTS Our study involved 50 patients; youngest patient was 33 years and oldest was 70 years. Majority of patients with foot gangrene were in the age group of 41 - 50 years, (22 cases) and highest number were males, (37 cases). Diabetes mellitus is the commonest aetiology accounting for 30 cases and commonest risk factor that confounds the disease process is smoking (17 cases). The commonest presentation was blackish discoloration of toe (s) along with cellulitis and ulceration (30 cases). The commonest organism isolated from culture is methicillin resistant Staphylococcal aureus (MRSA) (13 cases). Majority of the patients underwent Ray’s amputation (16 cases) in our study and majority had no post-operative wound complication (28 cases) within the minimum follow up period of 6 months. CONCLUSIONS We have therefore attempted in our study, to analyse the gangrene of the foot since diabetic cases and trauma cases are more in the rural setup and treatment of these gangrene cases is a challenging task as well. KEY WORDS Foot Gangrene, Amputation, Diabetes Mellitus

The Impact of Infectious Diseases Consultation on the Management and Outcomes of Pseudomonas aeruginosa Bacteraemia in Adults: A Retrospective Cohort Study.

Background: Pseudomonas aeruginosa bacteraemia (PAB) is associated with high mortality. The benefits of infectious diseases consultation (IDC) has been demonstrated in Staphylococcal aureus bacteraemia and other complex infections. Impact of IDC in PAB is unclear. This study aimed to evaluate the impact of IDC on the management and outcomes in patients with PAB.Methods: This is a retrospective cohort single-centre study from 1 November 2006 to 29 May 2019, in all adult patients admitted with first episode of PAB. Data collected included demographics, clinical management and outcomes for PAB and whether IDC occurred. In addition, 29 Pseudomonas aeruginosa (PA) stored isolates were available for Illumina whole genome sequencing to investigate if pathogen factors contributed to the mortality. Results: A total of 128 cases of PAB were identified, 71% received IDC. Patients who received IDC were less likely to receive inappropriate duration of antibiotic therapy (4.4% vs 67.6%; p<0.01), more likely to be de-escalated to oral antibiotic in a timely manner (87.9% vs 40.5%; p<0.01), undergo removal of infected catheter (27.5% vs 13.5%; p=0.049) and undergo surgical intervention (20.9% vs 5.4%, p=0.023) for source control. The overall 30-day all-cause mortality rate was 24.2% and was significantly higher in the no IDC group in both unadjusted (56.8% vs 11.0%, odds ratio [OR]=10.63, p<0.001) and adjusted analysis (adjusted OR=7.42; 95% confidence interval, 2.51-21.93 ). The genotypic analysis did not reveal any PA genetic features associated with increased mortality between IDC versus no IDC groups. Conclusion: Patients who received IDC for PAB had lower 30-day mortality, better source control and management was more compliant with guidelines. Further prospective studies are necessary to determine if these results can be validated in other settings.

Bacteriology and Antibiotic Susceptibility Patterns among Neonates Diagnosed of Omphalitis at a Tertiary Special Care Baby Unit in Western Uganda

Background. Newborn infections remain a major cause of morbidity and mortality among neonates in low-income countries. Clinical diagnosis for omphalitis in such settings is possible but this does not depict the microbiological characteristics of the involved organisms, and clinicians have often prescribed empirical antibiotics in neonates with omphalitis, despite an increasing burden of antibiotic resistance. Methods. A hospital-based cross-sectional study was conducted to evaluate the bacteriology and antibiotic susceptibility patterns among neonates diagnosed with omphalitis at the special care baby unit (SCBU) of Kampala International University-Teaching Hospital (KIU-TH), western Uganda from March to June 2019. Sixty-five (65) neonates with a clinical diagnosis of omphalitis were consecutively recruited in the study. Cord swabs were taken under sterile (aseptic) precautions from all neonates, and antibiotic susceptibility tests performed using the Kirby Bauer disk diffusion technique with commercially available antibiotics disks of ampicillin, cloxacillin, gentamicin, amikacin, cefotaxime, ceftriaxone, vancomycin, and imipenem on Mueller Hinton agar plates. The data was analyzed using STATA version 13.0, frequencies and proportions used to describe the variables. Results. Fifty-five, 55 (84.6%), neonates with suspected omphalitis had positive cord swab culture. Staphylococcal aureus (58.2%) was the commonest cause of omphalitis followed by Neisseria spp (16.4%), E. coli 6 (10.9%), Proteus spp (5.5%), Klebsiella spp (3.6%), Citrobacter spp (3.6%), and Haemophilus spp (1.8%) in decreasing frequency. Isolates were resistant to ampicillin (87.7%), gentamicin (54.4%), and cloxacillin (34.4%), the drugs recommended for use in neonates with suspected omphalitis. Conclusions. Staphylococcal aureus is still the predominant cause of omphalitis among neonates. There was high resistance to the commonly used antibiotics in the treatment of omphalitis among newborns. This study reemphasizes that clinicians should do cord swabbing for both culture and susceptibility tests among newborns with suspected omphalitis before initiation of antibiotics.