The curious case of the rare Citrobacter pasteurii isolated from an endangered primate in Brazil.

The genus Citrobacter comprises clinically important human pathogens but has been less frequently associated with wildlife infections. Citrobacter pasteurii was first identified as causing human diarrhea and remains rarely documented. In this study, a Gram-negative bacterial strain, named A318, was identified as causing diarrhea in a black lion tamarin. This strain was biochemically identified as Trabulsiella guamensis, a species of unusual nature, and was submitted to whole-genome characterization. Curiously, phylogenomic analysis showed that A318 strain belonged to the genus Citrobacter, with confirmation of the species C. pasteurii by average nucleotide identity (99.02 %) and digital DNA-DNA hybridization (93.80 %) analyzes. Cases of misidentification of C. pasteurii as Citrobacter youngae were detected and corrected in this study. In addition to the genome sequence of the type strain of C. pasteurii, only two others from the Australian cockle and Portuguese silver gull are publicly available. Single nucleotide polymorphism differences among all C. pasteurii indicated a highly diverse population. No acquired antimicrobial resistance genes and plasmid replicons were found. Therefore, our findings emphasize the importance of gold-standard methods for accurate identification and underscores the importance of continued surveillance and research to mitigate the risks posed by zoonotic and zooanthroponotic pathogens.

Infecção de trato urinário inferior por Citrobacter sp em cadela com hipoadrenocorticismo / Citrobacter sp lower urinary tract infection in a bitch with hypoadrenocorticism

Citrobacter sp. é um microrganismo frequentemente encontrado em vagina de cadelas, mas corresponde a menos de 3% do total de microrganismos isolados em urocultura. O hipoadrenocorticismo (HA) é uma doença endócrina incomum e que leva a poliúria e hipostenúria. O objetivo deste trabalho é relatar o caso de uma fêmea da espécie canina, da raça Teckel, 11 anos, atendida com queixa de urina de odor alterado há vários dias, além de vômito, diarreia e inapetência há três dias, e poliúria e polidipsia há 2 meses, com histórico de tratamento anterior com mitotano para hiperadrenocorticismo. O diagnóstico foi de ITU por Citrobacter sp., além de HA iatrogênico. Como destaques nos exames, relação sódio:potássio de 22,6 foi observada, sugestiva de HA, que foi confirmado por teste de estimulação com ACTH, além de urina inicialmente hipostenúrica (densidade 1,006), o que pode ser atribuído ao washout medular renal devido à hiponatremia causada pelo hipoadrenocorticismo. O tratamento foi feito com amoxicilina associada a ácido clavulânico por 20 dias, além da terapia específica para HA com prednisona e fludrocortisona, que foi continuado. A paciente recuperou-se bem, a densidade urinária aumentou após início do tratamento para HA e não houve recidiva da ITU em período de acompanhamento de 8 meses. Acredita-se que a baixa densidade urinária causada pelo HA tenha sido fator essencial para a oco

Citrobacter sp. is a normal constituent of bitches’ vagina, but it is related to less than 3% of total isolated microorganism in uroculture. Hypoadrenocorticism (HA) is an endocrine disease uncommonly diagnosed that leads to polyuria and hypostenuria. The aim of this work is report the case of a Teckel bitch, 11 years old, attended with complaint of altered urinary smell for several days, besides vomiting, diarrhea and inappetence for three days, and polyuria and polydispsia for two months, with previous mitotane treatment for hyperadrenocorticism. The diagnosis was Citrobacter UTI, besides iatrogenic HA. The most important exam results include sodium:potassium ratio of 22.6, suggestive of HA, that was confirmed by ACTH stimulation test. Besides, hypostenuria (urinary specific gravity – USG - of 1.006) was noted, attributed to renal medular washout due to hyponatremia seen in HA. Therapy comprised amoxicillin associated with clavulanic acid for 20 days, in addition to specific therapy for AH with prednisone and fludrocortisone. The patient recovery well, USG increased after the beginning of the treatment for HA and there was no UTI reinfection for a 8 month period. It is believed that low USG due to HA was essential for the occurrence of Citrobacter UTI.

Infecção de trato urinário inferior por Citrobacter sp em cadela com hipoadrenocorticismo / Citrobacter sp lower urinary tract infection in a bitch with hypoadrenocorticism

Citrobacter sp. é um microrganismo frequentemente encontrado em vagina de cadelas, mas corresponde a menos de 3% do total de microrganismos isolados em urocultura. O hipoadrenocorticismo (HA) é uma doença endócrina incomum e que leva a poliúria e hipostenúria. O objetivo deste trabalho é relatar o caso de uma fêmea da espécie canina, da raça Teckel, 11 anos, atendida com queixa de urina de odor alterado há vários dias, além de vômito, diarreia e inapetência há três dias, e poliúria e polidipsia há 2 meses, com histórico de tratamento anterior com mitotano para hiperadrenocorticismo. O diagnóstico foi de ITU por Citrobacter sp., além de HA iatrogênico. Como destaques nos exames, relação sódio:potássio de 22,6 foi observada, sugestiva de HA, que foi confirmado por teste de estimulação com ACTH, além de urina inicialmente hipostenúrica (densidade 1,006), o que pode ser atribuído ao washout medular renal devido à hiponatremia causada pelo hipoadrenocorticismo. O tratamento foi feito com amoxicilina associada a ácido clavulânico por 20 dias, além da terapia específica para HA com prednisona e fludrocortisona, que foi continuado. A paciente recuperou-se bem, a densidade urinária aumentou após início do tratamento para HA e não houve recidiva da ITU em período de acompanhamento de 8 meses. Acredita-se que a baixa densidade urinária causada pelo HA tenha sido fator essencial para a oco

Citrobacter sp. is a normal constituent of bitches vagina, but it is related to less than 3% of total isolated microorganism in uroculture. Hypoadrenocorticism (HA) is an endocrine disease uncommonly diagnosed that leads to polyuria and hypostenuria. The aim of this work is report the case of a Teckel bitch, 11 years old, attended with complaint of altered urinary smell for several days, besides vomiting, diarrhea and inappetence for three days, and polyuria and polydispsia for two months, with previous mitotane treatment for hyperadrenocorticism. The diagnosis was Citrobacter UTI, besides iatrogenic HA. The most important exam results include sodium:potassium ratio of 22.6, suggestive of HA, that was confirmed by ACTH stimulation test. Besides, hypostenuria (urinary specific gravity USG - of 1.006) was noted, attributed to renal medular washout due to hyponatremia seen in HA. Therapy comprised amoxicillin associated with clavulanic acid for 20 days, in addition to specific therapy for AH with prednisone and fludrocortisone. The patient recovery well, USG increased after the beginning of the treatment for HA and there was no UTI reinfection for a 8 month period. It is believed that low USG due to HA was essential for the occurrence of Citrobacter UTI.(AU)

Characterization of a multidrug resistant Citrobacter amalonaticus clinical isolate harboring blaNDM-1 and mcr-1.5 genes.

A multidrug resistant isolate, identified as Citrobacter amalonaticus using MALDI-TOF MS and confirmed by genomic analysis, was recovered from a pediatric patient in a hospital from Buenos Aires, Argentina. By whole-genome sequencing a total of 16 resistance genes were detected, including blaNDM-1 and mcr-1.5. To the best of our knowledge this is the first description of these two genes together in a clinical isolate of the Citrobacter genus.

[Characterization and distribution of Citrobacter species in a university hospital]. / Caracterización y distribución de especies de Citrobacter en un hospital universitario.

OBJECTIVE: [corrected] a) To identify Citrobacter strains following the conventional biochemical reaction of Brenner and col; b) to evaluate the sensitivity and specificity of the O'Hara's method compared with Brenner's method, and c) to determine the rate and distribution of the strains in the clinical isolates. MATERIAL AND METHODS: One hundred and twenty two clinical isolates, characterized as Citrobacter spp. were collected between May of 1994 and August of 1997. Clinical isolates included inpatients and outpatients from Hospital de Clínicas. Strains were identified following the methods of Brenner and O'Hara. RESULTS: Methods of Brenner identified 111 of 122 strains: C. freundii 59 of 111; C. koseri 18 of 111; C. werkmanii 15 of 111; C. braakii 9 of 111; C. youngae 6 of 111 and C. amalonaticus 4 of 111. O'Hara's methods identified 104 of 111 strains (94%). C. freundii was recovered most frequently from urine and feces (p Fisher < 0.026 and 0.039 respectively), while C. koseri was isolated from urine principally (p Fisher < 0.0372). CONCLUSIONS: The genus Citrobacter is an important opportunistic pathogen that can be identified in clinical microbiology laboratories using O'Hara's method.

[Bacteremic pneumonia caused by Citrobacter diversus: report of a case]. / Neumonía bacterémica por Citrobacter diversus: caso clínico.

A 61 year old male with a localized gastric cancer developed a post-operative pneumonia by C. diversus which was isolated from blood and from bronchoalveolar lavage. A satisfactory response was observed after treatment with penicillin and amikacin. A brief review of the literature concerning the clinical relevance of infections by this unusual agent is offered.