A wolf in sheep's clothing: Dogs confer an unrecognized risk for their immunocompromised master

Complex and severe infection in a 67-year-old liver transplant recipient due to Cunninghamella elegans, Bordetella bronchiseptica, and Pneumocystis jirovecii

INTRODUCTION

Cunninghamella elegans infections cause rare and severe mucormycosis. Bordetella bronchiseptica and Pneumocystis jirovecii relate to pneumonia. They are all clinically uncommon pathogens and no reports of co-infections have been reported.

CASE PRESENTATION

Here we present a case of a 67-year-old male patient who initially presented with fever, chills, and mild cough. B. bronchiseptica, P. jirovecii, Aspergillus fumigatus, and human alphaherpesvirus 1 (HSV1) were detected by clinical metagenomic next-generation sequencing (mNGS) of his bronchoalveolar lavage fluid (BLAF). Despite receiving anti-infective treatment, the patient rapidly developed respiratory failure and was transferred to the intensive care unit. Subsequent mNGS testing further revealed the presence of C. elegans, indicating that different pathogens played dominant roles at various stages of the disease progression. The routine culture also identified several of the above pathogens, but the results were reported much later than those of mNGS. Eventually, imaging findings and symptoms of the patient improved with comprehensive antibiotic coverage, and he was transferred to a lower-level hospital for rehabilitation treatment.

CONCLUSIONS

This is the first detailed report of the combined infection of B. bronchiseptica, P. jirovecii, and C. elegans. During the treatment process, we also observed rare and unusual neurological side effects: visual and auditory hallucinations, restlessness, and aphasia. Also, the case indicates that traditional methods are insufficient for the etiological diagnosis needs of critical and severe patient populations, and timely use of mNGS should be recommended.

The contribution of BvgR, RisA, and RisS to global gene regulation, intracellular cyclic-di-GMP levels, motility, and biofilm formation in Bordetella bronchiseptica

Bordetella bronchiseptica is a highly contagious respiratory bacterial veterinary pathogen. In this study the contribution of the transcriptional regulators BvgR, RisA, RisS, and the phosphorylation of RisA to global gene regulation, intracellular cyclic-di-GMP levels, motility, and biofilm formation were evaluated. Next Generation Sequencing (RNASeq) was used to differentiate the global gene regulation of both virulence-activated and virulence-repressed genes by each of these factors. The BvgAS system, along with BvgR, RisA, and the phosphorylation of RisA served in cyclic-di-GMP degradation. BvgR and unphosphorylated RisA were found to temporally regulate motility. Additionally, BvgR, RisA, and RisS were found to be required for biofilm formation.

Immunocompromised Children and Young Patients Living with Pets: Gaps in Knowledge to Avoid Zoonosis

Methods

A cross-sectional, observational study was performed in a large tertiary hospital in Madrid, including immunosuppressed patients from different regions of Spain. The participants were asked to complete an online questionnaire.

Results

Two hundred and eighty-four responses were received: 62.3% solid organ transplantation (177/284), 22.8% hematopoietic stem cell transplantation (65/284), and 14.8% inborn errors of immunity (42/284). The median age was 11 years (interquartile range 5.9-15.4), and 55% were boys (156/284). Up to 45% (130/284) of the respondents lived with 201 pets (74% of them dogs and cats). Half of the patients owning dogs or cats did not comply with at least one of the recommendations regarding vaccination, deworming, feeding, and/or veterinarian recommended controls. The poorest findings were related to deworming regimens. Only 42.8% (117/273) of the participants received specific recommendations from their healthcare professionals about companion animals. However, up to 97% of the families considering acquiring a pet did so when the professional did not contraindicate it (31/32), while 72% of the families having pets got rid of their pets when they were advised against animals (8/11).

Conclusions

Pet ownership is frequent among immunocompromised children. They presented risky exposures for acquiring zoonoses, and basic veterinary recommendations were not frequently followed. The opinion of professionals significantly influenced the decision to acquire pets, but less than half of the families received recommendations in this regard.