Bacteremia caused by Stomatococcus mucilaginosus: report of seven cases and review of the literature

Treatment and outcomes of peritonitis due to Rothia species in patients on peritoneal dialysis: A systematic review and multicentre registry analysis

Peritoneal dialysis (PD)-associated peritonitis remains a severe complication of PD. Although peritonitis due to Rothia spp. is rare, the treatment recommendations and outcomes are uncertain. Our study aims to review (1) published literature on peritonitis caused by Rothia spp. and (2) reported cases of peritonitis due to Rothia spp. in patients on PD in Australia and New Zealand. A literature search of PubMed, Scopus, Embase and Google Scholar for articles published between January 1949 and February 2022 was conducted. To be eligible, articles had to describe antibiotic therapy and treatment outcomes in all PD patients for peritonitis caused by Rothia or Stomatococcus spp. Data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry of PD patients who developed peritonitis due to Rothia spp. between July 2011 and May 2020 were also reviewed. A total of 12 articles and 28 episodes were identified from the literature search and ANZDATA registry analysis, respectively. Over 60% of the peritonitis cases due to Rothia spp. were from the Rothia mucilaginosa species (8/12 and 17/28, respectively), while Rothia dentocariosa was the second most commonly identified species in both the literature search and the ANZDATA registry analysis (4/12 and 5/28, respectively). A majority 8 (66.7%) of the articles in the literature search employed a combination antibiotic regimen, while the remaining 4 (33.3%) used a single antibiotic regimen. In contrast, most of the episodes, 22 (78.6%) described in the ANZDATA registry analysis, employed a single antibiotic regimen, and only 6 (21.4%) episodes were treated with a combination antibiotic regimen. The duration of antibiotic therapy ranged from 2 to 3 weeks in the literature search, and 1 to 3 weeks in the ANZDATA registry. While no deaths within 30 days of developing peritonitis were reported, catheter removal was reported in three (25%) and two (7.1%) episodes in both the literature search and the ANZDATA registry analysis, respectively, of which the majority occurred in patients treated for ≤2 weeks. PD-associated peritonitis due to Rothia spp. is uncommon and associated with relatively good outcomes. Antibiotic treatment for 3 weeks is associated with better outcomes.

Characterization of the Rothia spp. and their role in human clinical infections

The genus Rothia are emerging as opportunistic pathogens associated with various infections in immunocompromised and immunocompetent individuals. This review describes the taxonomy, cell wall structure, pathogenesis, phenotypic and molecular characteristics, clinical diseases, treatment and, as well as, the related genera that may be misidentified by Rothia species.

Rothia spp. infective endocarditis: A systematic literature review

OBJECTIVE

To describe the epidemiological, clinical, microbiological, and therapeutic features and outcomes of Rothia infective endocarditis (RIE) and extracardiac infections (ECRI).

METHODS

We performed a systematic literature review of published cases of RIE and ECRI.

RESULTS

After inclusion of a personal case report, 51 cases of RIE and 215 cases of ECRI were reported. Compared with ECRI patients, RIE patients were significantly more often males (80% versus 59%), intravenous drug users (IVDU) (20% versus 3%), immunocompetent (76% versus 31%), and infected with R. dentocariosa (55% versus 13%) but lacked significant differences with regard to median age (45 years [6-79]), rate of orodental abnormalities (33%), and six-month mortality (14%). Following microbiological documentation, RIE was most often treated with a beta-lactam antibiotic alone (39%) for a median duration of six weeks and required surgery in 39% of cases.

CONCLUSION

RIE is rare and likely secondary to a dental portal of entry or cutaneous inoculation in IVDU. Its prognosis seems to be favorable.

Rothia mucilaginosa Infections in Pediatric Cancer Patients

We performed a retrospective study to determine the epidemiology of Rothia mucilaginosa infections among pediatric cancer patients. Over 20 years, 37 cases were identified; 27% developed complications, but there was no infection-related mortality. All cases were successfully treated with vancomycin.

Rothia bacteremia: a 10-year experience at Mayo Clinic, Rochester, Minnesota

Rothia spp. are Gram-positive cocco-bacilli that cause a wide range of serious infections, especially in immunocompromised hosts. Risk factors for Rothia mucilaginosa (previously known as Stomatococcus mucilaginosus) bacteremia include prolonged and profound neutropenia, malignancy, and an indwelling vascular foreign body. Here, we describe 67 adults at the Mayo Clinic in Rochester, MN, from 2002 to 2012 with blood cultures positive for Rothia. Twenty-five of these patients had multiple positive blood cultures, indicating true clinical infection. Among these, 88% (22/25) were neutropenic, and 76% (19/25) had leukemia. Common sources of bacteremia were presumed gut translocation, mucositis, and catheter-related infection. One patient died with Rothia infection. Neutropenic patients were less likely to have a single positive blood culture than were nonneutropenic patients. Antimicrobial susceptibility testing was performed on 21% of the isolates. All of the tested isolates were susceptible to vancomycin and most beta-lactams; however, four of six tested isolates were resistant to oxacillin. There was no difference between the neutropenic and nonneutropenic patients in need of intensive care unit care, mortality, or attributable mortality.

Significant morbidity and mortality attributable to rothia mucilaginosa infections in children with hematological malignancies or following hematopoietic stem cell transplantation

Rothia mucilaginosa is a gram-positive coccus that poses a diagnostic challenge and often requires DNA pyrosequencing for diagnosis as it can be easily mistaken for coagulase-negative staphylococci on initial culture results. While it is often times normal human oral and upper respiratory tract microbiota, it can be a virulent pathogen in immunocompromised patients. Most commonly, it causes bacteremia (catheter and non-catheter related) and meningitis in these patients. Our objective was to report the incidence of R. mucilaginosa infections in neutropenic children with hematological malignancies or following hematopoietic stem cell transplantation at a major children's hospital. We report 11 patients in this cohort who developed clinically significant R. mucilaginosa infections, including three deaths directly attributable to this microorganism. Three patients developed significant neurological involvement, accounting for two of the deaths, and one patient died of disseminated infection. Except for one, all patients had severe neutropenia, central line catheters, and mucosal breakdown at the time of infection. Patients who succumbed never achieved neutrophil recovery. In conclusion, R. mucilaginosa can lead to life-threatening infections in immunocompromised hosts, especially in profoundly neutropenic patients.

Eight cases of lower respiratory tract infection caused by Stomatococcus mucilaginosus

Stomatococcus mucilaginosus was isolated from 8 patients suffering from lower respiratory tract infections over a 4-y period (1999-2003). The infections ranged from mild cases of pneumonia to a life-threatening case of recurrent lung abscesses in a neutropenic patient. The various strains were cultured from specimens obtained by bronchoscopy, blood, and sputum specimens. All strains were fully susceptible to rifampicin, vancomycin and gentamicin. They showed variable susceptibility to penicillin and ciprofloxacin. S. mucilaginosus is likely to be under-reported as a pathogen due to difficulties in obtaining samples for culture as well as misidentification due to its biochemical characteristics.

Stomatococcus mucilaginosus septicemia in a patient with acute lymphoblastic leukaemia

A 16-year-old patient with acute lymphoblastic leukaemia which had relapsed for the third time developed clinical signs and symptoms of septicemia during a period of neutropenia. The patient had signs of oral mucositis, and Stomatococcus mucilaginosus was isolated from blood cultures. The patient responded well to antibiotic therapy. The biochemical characteristics and antimicrobial susceptibility patterns of 68 other pharyngeal isolates of Stomatococcus mucilaginosus from immunocompromised patients are presented.

Advances in medical and antibiotic management of infective endocarditis

Infective endocarditis remains a serious medical problem despite advancements in laboratory detection, echocardiographic techniques, and newer antibiotic agents. This article summarizes the microbial agents in infective endocarditis, in addition to developments in medical and antibiotic management.

Study of Stomatococcus mucilaginosus isolated in a hospital ward using phenotypic characterization

Thirty-one isolates of Stomatococcus mucilaginosus were cultured from the blood (n = 6), throat (n = 23) and sputum (n = 2) of 18 hospitalized patients, 13 of whom were neutropaneic and five of whom were non-neutropaneic. Antibiotic susceptibility testing, performed by means of a broth microdilution method, showed that the minimal inhibitory concentrations (MICs) of ciprofloxacin were > or = 4 mg/l for the isolates collected from neutropaenic patients. All these patients received ciprofloxacin as part of their prophylactic regimen. In contrast, the MICs for four of five isolates collected from non-neutropaenic patients, none of whom were receiving ciprofloxacin, were < or = 2 mg/l. In addition, 14 of the 31 isolates were cultured from seven neutropaenic patients, admitted to the same ward over a 12-week period. To evaluate possible cross-acquisition of strains between patients, cluster analysis of all 31 isolates was performed using phenotypic characteristics, MIC values and acid production from carbohydrates (API 50 CH). Overall, 22 isolate clusters were distinguished. In five of 18 patients, two or more isolates were cultured which belonged to different clusters. In only one patient, identical isolates were cultured from blood and from the throat. All six isolates of cluster 7 were cultured within the aforementioned 12-week period from three neutropaenic patients. These data support the possibility of cross-acquisition of strains between patients although its frequency seems to be low.

Antimicrobial susceptibilities of Stomatococcus mucilaginosus and of Micrococcus spp

The in vitro susceptibilities of 63 isolates of Stomatococcus mucilaginosus and of 188 isolates of Micrococcus spp. to 18 antimicrobial agents were determined by the agar dilution method. Many beta-lactams, imipenem, rifampin, and the glycopeptides were shown to be active in vitro against Stomatococcus and Micrococcus isolates, whereas the activities of antibiotics such as some aminoglycosides, erythromycin, and fosfomycin against an important number of these microorganisms are limited.

Stomatococcus mucilaginosus lower respiratory tract infection in a patient with AIDS

We describe a case of recurrent Stomatococcus mucilaginosus lower respiratory tract infection in a patient with AIDS. Apart from S. mucilaginosus no other pathogens were found to account for infection. There was a rapid response to rifampicin, the organism being resistant to penicillin, co-trimoxazole and ciprofloxacin. Infections caused by this organism are increasingly described, but there are few reports of lower respiratory tract infection.

Association of Stomatococcus mucilaginosus with cholangitis

The first case of cholangitis in which Stomatococcus mucilaginosus was cultured from bile is reported. A 64-year-old male became icteric and was shown to have gallstones in the gallbladder and a common bile duct stone which was removed endoscopically. As the patient remained icteric for a month thereafter the gallbladder with stones was removed. No common bile duct stone was shown by cholangiography perioperatively. The liver biopsy revealed cholangitis and Stomatococcus mucilaginosus was grown from the bile. The patient was cured by cholecystectomy without any antimicrobial therapy.

Stomatococcus mucilaginosus septicemia in two bone marrow transplanted patients

A 44-year-old man with chronic myeloid leukemia and a 10-year-old boy with adrenoleukodystrophy, both admitted for bone marrow transplantation in December 1992, developed clinical signs of septicemia within 2 weeks after transplantation. Three strains of Stomatococcus mucilaginosus were isolated from blood cultures. These were among the first cases of S. mucilaginosus infection diagnosed at our Laboratory and the first reported from Scandinavia. S. mucilaginosus is part of the endogenous oral flora. Both patients had signs of oral mucositis. All 3 strains were isolated earlier with the Laboratory's present blood culture system, compared with the one in use before spring 1992.