Extraintestinal infections caused by nontyphoidal Salmonella from a tertiary care center in India

Clinical-Microbiological Study of Nontyphoidal Salmonella Infections from Karnataka, India

Background

Nontyphoidal salmonella (NTS) are responsible for food-borne gastroenteritis and bacteremia, in immunosuppressed individuals. Antibiotic resistance in NTS is on the rise. This study reports the prevalence and antimicrobial susceptibility of nontyphoidal salmonella in clinical samples. Study Design. This is a hospital record-based cross-sectional, retrospective study.

Methods

In our study, inpatient samples such as blood (n = 13546), urine (n = 11,333), pus (n = 1,010), and stool (n = 926) samples were cultured to isolate etiological agents in the microbiology department from January 2017 to June 2019. Relevant details such as duration of fever, platelet count, hemoglobin, WBC count, immune status, and mode of treatment were noted from the medical records. Data were analyzed, and continuous variables were expressed as mean and categorical variables as percentages.

Results

A total of 24 NTS serovars were isolated, which included ten isolates from blood, five each from urine and pus, and four from stool samples. Of the NTS, five were Salmonella enterica subsp. enterica, three were S.enterica serovar Typhimurium, one was S.enterica subsp. diarizonae, and 15 S.enterica serovars could not be serologically differentiated. All were susceptible to ampicillin, chloramphenicol, and cefuroxime. However, 16.6% of NTS was resistant to ceftriaxone, 4% to cotrimoxazole, 58% to ciprofloxacin, and 75% to nalidixic acid.

Conclusions

A low prevalence of NTS responsible for invasive infections is seen in this part of the country. Few isolates were resistant to more than one antibiotic. A higher rate of resistance to ceftriaxone is the cause of concern. Awareness of the distribution of NTS serogroups is of epidemiological and public health significance.

Extra-intestinal salmonellosis in a tertiary care centre in South India

Background and Objectives

Extra-intestinal salmonellosis is associated with higher case fatality and is underestimated in the developing countries like India. Here we present a case series of bacteriologically proven extra-intestinal salmonellosis managed at our institute over the past two years.

Materials and Methods

Retrospective analysis of bacteriologically proven extra-intestinal salmonellosis over two years between January 2020 to December 2021 was carried out. Medical records were reviewed for site of infection, evidence of any underlying or predisposing illnesses and antimicrobial susceptibility report.

Results

Eight patients were diagnosed with extra-intestinal salmonellosis. Male to female ratio was 3:1. Mean age was 44 years. Four were typhoidal and four were nontyphoidal Salmonellae. The extra-intestinal sites involved were purulent aspirates from scrotum, caecum, perianal region, intraperitoneal collection, synovium, and urine. Predisposing factors include chronic myeloid leukemia, HIV and gastric malignancy. All deep seated abscess required surgical intervention. All typhoidal Salmonella (n=4) were sensitive to cotrimoxazole, ampicillin, ceftriaxone. Among nontyphoidal Salmonella, one was resistant to cotrimoxazole; two were resistant to ampicillin, ceftriaxone and three resistant to ciprofloxacin.

Conclusion

The diagnosis of extra-intestinal salmonellosis requires a high degree of clinical suspicion and should be included in the differential diagnosis in patients with deep-seated abscesses.

The Rise of Non-typhoidal Salmonella Infections in India: Causes, Symptoms, and Prevention

Non-typhoidal Salmonella infections (NTS) are a growing concern in India, posing a significant health risk to the population. These infections are becoming more common at worrisome rates, primarily because of inadequate surveillance. Salmonella non-typhoidal causes severe gastroenteritis and can even cause invasive infections, such as bacteremia, and focal infections, such as meningitis and septic arthritis, and is acquired through contaminated food and water sources. From moderate to severe, the symptoms might vary. Certain serovars exhibit a stronger propensity for specific syndromes, with serious infections more commonly observed in vulnerable populations. Consuming contaminated food, using inadequate sanitation procedures while handling meat from animals slaughtered, and contaminated water supplies are some of the causes of these diseases. Proper food and water treatment, better sanitary facilities, public awareness campaigns, and adherence to food safety laws are all part of prevention measures. The issue of antimicrobial resistance further emphasizes the necessity for prudent antibiotic usage. The Indian government has put in place programs including public awareness campaigns, better sanitary facilities, and stricter food safety laws. In the future, efforts should, however, concentrate on improving laws, boosting hygienic practices, and funding the development of new medicines and vaccines. These actions will lessen the burden of NTS infections in India by assisting in their prevention and management. This review aims to understand the reasons for this growing tendency, which is essential for creating efficient control and prevention strategies.

Ceftriaxone Resistant Salmonella enterica Serovar Kentucky as a Cause of Bacteremia and Gastroenteritis: A Case Report

Salmonella enterica serovar Kentucky is an emerging human pathogen in developed countries and also a concern for public health in developing countries. Although genus Salmonella is usually susceptible to many antimicrobial agents, a recent increase in resistance has become a cause for concern. A case of ceftriaxone resistant Salmonella enterica serovar Kentucky causing bacteremia and acute gastroenteritis is reported in this paper. The Salmonella Kentucky isolate in this case was resistant to most classes of antibiotics. This is the first case report of Salmonella enterica serovar Kentucky resistant to ceftriaxone. Multidrug resistant patterns of Salmonella Kentucky are observed globally. Awareness of various nontyphoid Salmonella causing human infections is of utmost importance, because delayed identification, serotyping, and susceptibility testing may delay the administration of antibiotics leading to worsening outcomes.

Isa WYH. The Unusual Cause of Cardiac Tamponade

We present a previously healthy young man with cardiac tamponade. He underwent emergency pericardiocentesis. The pericardial fluid was exudative, and Salmonella sp. was grown on both pericardial and blood cultures. Further investigations revealed that this patient had classical Hodgkin lymphoma, which explains his immunocompromised state predisposing him to this infection. (Level of Difficulty: Advanced.).

An emerging threat of ceftriaxone-resistant non-typhoidal salmonella in South India: Incidence and molecular profile

Background

Non-typhoidal Salmonella (NTS) infection is a serious public health problem globally. Although NTS infections are self-limited, antimicrobial therapy is recommended for severe infections and immunocompromised patients. Antimicrobial resistance (AMR) in these pathogens further limits its therapeutic options. Here, we report an incidence of ceftriaxone resistance in NTS over the past 9 years in a southern Indian region.

Materials and Methods

Molecular mechanisms of resistance in ceftriaxone-resistant NTS have been tested by both phenotypic and molecular methods. Minimum inhibitory concentration was determined by the E-test and broth microdilution method. AMR gene markers of β-lactamases such as AmpCs (blaMOX, blaCMY, blaDHA, blaFOX, blaACC and blaACT) and extended-spectrum β-lactamases (ESBLs) (blaSHV, blaTEM, blaVEB, blaPER, blaCTXM-1like,blaCTXM-2like, blaCTXM-8like, blaCTXM-9like and blaCTXM-25like) were screened. The presence of IncH12 and IncI1 plasmid was also analysed.

Results

The study reports a 5% prevalence of ceftriaxone resistance in NTS. The most common serogroup was Salmonella Group B followed by Salmonella Group E and Salmonella group C1/C2. The occurrence of blaCTX-M-1, blaTEM, blaCMY and blaSHV genes was observed in 54%, 54%, 48% and 3% of the isolates, respectively. Interestingly, few isolates carried dual resistance genes (ESBLs and AmpCs). IncH12 and IncI1 plasmid was identified in isolates carrying ESBL and AmpC genes, respectively.

Conclusion

This study shows that ceftriaxone resistance is mainly mediated by β-lactamases such as ESBL and AmpC. As the incidence of ceftriaxone resistance is rising gradually over the years, it is imperative to monitor the AMR in this species.