Haemophilus parainfluenzae endocarditis in young adults

An unusual presentation of subacute Haemophilus parainfluenzae endocarditis in a low-risk woman treated by minimally invasive mitral valve repair: a case report

BACKGROUND

HACEK endocarditis is usually insidious and can often be difficult to diagnose due to the slow-growing nature of the organisms. This report presents our experience in treating a patient with Haemophilus parainfluenzae endocarditis.

CASE PRESENTATION

We describe the case of a previously fit and well 23 year-old woman who presented to her local emergency department with a four-week history of persistent febrile illness. She had associated nausea, vomiting, and lethargy. This was preceded by an episode of mucopurulent rhinorrhoea. She was treated empirically with oral amoxicillin for a putative diagnosis of rhinosinusitis. Initially, her symptoms abated, however, she was readmitted with high fevers and a new pansystolic murmur. Transthoracic echocardiography revealed a large, mobile, echogenic mass, tethered to the posterior mitral valve leaflet (PMVL) and mild mitral regurgitation (MR). On examination, she had multiple non-tender, erythematous macules on the plantar surface of her feet, consistent with Janeway lesions. Two separate blood cultures grew H. parainfluenzae. Infectious diseases recommended a four-week course of intravenous ceftriaxone. Transesophageal echocardiography demonstrated a perforation within the P3 segment of the PMVL. Subsequently, the patient underwent mitral valve repair surgery with an uneventful recovery.

CONCLUSIONS

Our case highlights the importance of promptly diagnosing HACEK endocarditis. A prolonged course of antibiotic therapy can be lifesaving, and surgery is often necessary to address complications such as perforation within the mitral valve leaflets. In our patient, we were able to perform a sliding P2 leaflet plasty for good quality repair of the mitral valve, through a minimally invasive right anterior thoracotomy.

Virulent endocarditis due to Haemophilus parainfluenzae: A systematic review of the literature

BACKGROUND

Haemophilus parainfluenzae (HPI) belongs to the HACEK (Haemophilus spp., Aggregatibacter spp., Cardiobacterium spp., Eikenella spp., and Kingella spp.) group of organisms. The HACEK group of organisms are a part of the oropharyngeal flora and can cause invasive opportunistic infection such infective endocarditis (IE) in hosts with compromised immunological barriers.

AIM

To perform a 20-year systematic review of the literature characterizing the clinical presentation, epidemiology and prognosis of HPI IE.

METHODS

We performed a systematic review of Medline, Pubmed, Scopus and Embase from 2000 to 2022 to identify all cases of HPI IE.

RESULTS

Thirty-nine adult cases were identified. HPI IE was found to affect males slightly more than females and is common in patients with predisposing risk factors such as underlying valvular abnormalities. It mostly affected the mitral valve and had an indolent course; significantly sized vegetations (> 1 cm) developed in most cases. Central nervous system septic embolization was common. It had a favorable prognosis compared to staphylococcal and streptococcal IE.

CONCLUSION

Clinicians should be attentive to the indolent course of HPI IE and the presence of predisposing risk factors in order to allow for timely management.

The Difference of Gut Microbiota and Their Correlations With Urinary Organic Acids Between Autistic Children With and Without Atopic Dermatitis

Autism is a kind of biologically based neurodevelopmental condition, and the coexistence of atopic dermatitis (AD) is not uncommon. Given that the gut microbiota plays an important role in the development of both diseases, we aimed to explore the differences of gut microbiota and their correlations with urinary organic acids between autistic children with and without AD. We enrolled 61 autistic children including 36 with AD and 25 without AD. The gut microbiota was sequenced by metagenomic shotgun sequencing, and the diversity, compositions, and functional pathways were analyzed further. Urinary organic acids were assayed by gas chromatography–mass spectrometry, and univariate/multivariate analyses were applied. Spearman correlation analysis was conducted to explore their relationships. In our study, AD individuals had more prominent gastrointestinal disorders. The alpha diversity of the gut microbiota was lower in the AD group. LEfSe analysis showed a higher abundance of Anaerostipes caccae, Eubacterium hallii, and Bifidobacterium bifidum in AD individuals, with Akkermansia muciniphila, Roseburia intestinalis, Haemophilus parainfluenzae, and Rothia mucilaginosa in controls. Meanwhile, functional profiles showed that the pathway of lipid metabolism had a higher proportion in the AD group, and the pathway of xenobiotics biodegradation was abundant in controls. Among urinary organic acids, adipic acid, 3-hydroxyglutaric acid, tartaric acid, homovanillic acid, 2-hydroxyphenylacetic acid, aconitic acid, and 2-hydroxyhippuric acid were richer in the AD group. However, only adipic acid remained significant in the multivariate analysis (OR = 1.513, 95% CI [1.042, 2.198], P = 0.030). In the correlation analysis, Roseburia intestinalis had a negative correlation with aconitic acid (r = -0.14, P = 0.02), and the latter was positively correlated with adipic acid (r = 0.41, P = 0.006). Besides, the pathway of xenobiotics biodegradation seems to inversely correlate with adipic acid (r = -0.42, P = 0.18). The gut microbiota plays an important role in the development of AD in autistic children, and more well-designed studies are warranted to explore the underlying mechanism.

A study of various factors affecting satellitism tests of Haemophilus influenzae and Haemophilus parainfluenzae using Staphylococcus aureus as the source of NAD

Many factors affecting satellitism tests are unclear, and it is difficult to avoid misidentification, even if the medium is properly selected. We investigated the factors causing false-positive results for Haemophilus influenzae and false-negative results for Haemophilus parainfluenzae in the satellitism tests using Staphylococcus aureus as the source of nicotinamide adenine dinucleotide (NAD). H. influenzae (four reference strains and 47 clinical isolates), H. parainfluenzae (two reference strains and 67 clinical isolates), four different media, and two strains of S. aureus revived on two different media were used in this study. The type of medium used to revive S. aureus was the most common factor causing false-positive results for H. influenzae, followed by different strains of S. aureus and the type of medium used for the experiment. The production of false-negative results for H. parainfluenzae was only related to the medium used in the experiment. To improve the accuracy of the tests in routine laboratories, using S. aureus as the source of NAD, tryptic soy agar, and S. aureus (ATCC 25923) revived on nutrient agar should be adopted.

Haemophilus parainfluenzae endocarditis in a low-risk woman: a case report

Haemophilus parainfluenzae endocarditis is a rare but dangerous disease. With this work, we intend to show the importance of early diagnosis and appropriate treatment in order to avoid complications. We also highlight the importance of local epidemiology to choose antibiotic prophylaxis for high-risk procedures in selected predisposed patients.

Emergence of multidrug resistance among Haemophilus parainfluenzae from respiratory and urogenital samples in Barcelona, Spain

Haemophilus parainfluenzae (HPAR) is a Gram-negative bacterium that can become an opportunistic urogenital pathogen. Recently, multidrug resistant (MDR) strains have emerged. We aim to analyse the epidemiology of HPAR at Hospital Universitari de Bellvitge between 2013 and 2017 to determine its putative role in sexually transmitted infections (STI). Strains were classified by sample origin, and antimicrobial susceptibility was performed by disk-diffusion tested on Mueller-Hinton Fastidious. MDR was defined as the resistance of the antimicrobial to three or more antibiotic class. Molecular typing was performed by pulsed-field gel electrophoresis (PFGE) after restriction with SmaI and Cfr9I. We classified 944 HPAR isolates as being of urogenital (n = 175; 18.5%), respiratory (n = 719; 76.2%), or other (n = 50; 5.3%) origins. Among the urogenital isolates, 50 (28.6%) were MDR, which was significantly higher than that found in respiratory samples (40/719; 5.6%; p < 0.01). The frequency of MDR increased progressively among urogenital samples from 13.3% (2013) to 33.3% (2017) (r = 0.8; p = 0.035). The resistance rates for all 944 episodes were significantly higher for cotrimoxazole (51.4%), tetracycline (46.3%), chloramphenicol (28.0%), ciprofloxacin (21.1%), and ampicillin (20.6%). After PFGE, no clonal relationship was found. Clinical charts were available for 40 symptomatic patients with MDR HPAR infections presenting mostly urethritis (n = 26; 65.0%). In all cases, symptoms were treated effectively with combination therapy. Furthermore, in 10 of those patients with urethritis, MDR HPAR was the only potential pathogen to be identified. The emergence of MDR HPAR is a matter of concern, and the detection as a single pathogen highlights its putative role as cause of STI.

Multisystem organ failure secondary to Haemophilus parainfluenzae infective endocarditis on an ICD lead: A case report

Infection of implanted cardiac devices (ICD) is an unusual but life threatening event, rarely caused by Haemophilus parainfluenzae. While clinical presentation varies widely, infective endocarditis (IE) involving an ICD lead requires aggressive resuscitation and a multidisciplinary approach. We present a case of a 33-year-old intravenous drug user who presented in multisystem organ failure secondary to infective endocarditis on an ICD lead. This patient had a complicated hospital course requiring removal of her ICD, highlighting the dramatic presentation of this clinical state.

Alterations of oral microbiota distinguish children with autism spectrum disorders from healthy controls

Altered gut microbiota is associated with autism spectrum disorders (ASD), a group of complex, fast growing but difficult-to-diagnose neurodevelopmental disorders worldwide. However, the role of the oral microbiota in ASD remains unexplored. Via high-throughput sequencing of 111 oral samples in 32 children with ASD and 27 healthy controls, we demonstrated that the salivary and dental microbiota of ASD patients were highly distinct from those of healthy individuals. Lower bacterial diversity was observed in ASD children compared to controls, especially in dental samples. Also, principal coordinate analysis revealed divergences between ASD patients and controls. Moreover, pathogens such as Haemophilus in saliva and Streptococcus in plaques showed significantly higher abundance in ASD patients, whereas commensals such as Prevotella, Selenomonas, Actinomyces, Porphyromonas, and Fusobacterium were reduced. Specifically, an overt depletion of Prevotellaceae co-occurrence network in ASD patients was obtained in dental plaques. The distinguishable bacteria were also correlated with clinical indices, reflecting disease severity and the oral health status (i.e. dental caries). Finally, diagnostic models based on key microbes were constructed, with 96.3% accuracy in saliva. Taken together, this study characterized the habitat-specific profile of the oral microbiota in ASD patients, which might help develop novel strategies for the diagnosis of ASD.