Systematic Reviews
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Oct 26, 2022; 14(10): 546-556
Published online Oct 26, 2022. doi: 10.4330/wjc.v14.i10.546
Virulent endocarditis due to Haemophilus parainfluenzae: A systematic review of the literature
Abdulbaril Olagunju, Jake Martinez, Dorothy Kenny, Philip Gideon, Farouk Mookadam, Samuel Unzek
Abdulbaril Olagunju, Dorothy Kenny, Department of Internal Medicine, Creighton University School of Medicine, Phoenix, AZ 85013, United States
Jake Martinez, Philip Gideon, Farouk Mookadam, Samuel Unzek, Department of Cardiology, Heart Center, University of Arizona College of Medicine-Phoenix, Banner University Medical Center, Phoenix, AZ 85006, United States
Farouk Mookadam, Department of Cardio-oncology, Banner MD Anderson Cancer Center, Phoenix, AZ 85006, United States
Author contributions: Olagunju A and Mookadam F designed the research; Olagunju A, Kenny D, Martinez J, Gideon P, and Unzek S performed the research; Olagunju A, Kenny D and Mookadam F analyzed the data; Olagunju A, Kenny D, Martinez J and Mookadam F wrote the paper.
Conflict-of-interest statement: All authors declare that they have no conflict of interest.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Abdulbaril Olagunju, MD, Doctor, Internal medicine, Creighton University School of Medicine, 350 W Thomas Road, Phoenix, AZ 85013, United States. ab.dapoola@gmail.com
Received: July 2, 2022
Peer-review started: July 2, 2022
First decision: August 1, 2022
Revised: August 27, 2022
Accepted: September 15, 2022
Article in press: September 15, 2022
Published online: October 26, 2022
Processing time: 109 Days and 4.4 Hours
Abstract
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.

Keywords: Haemophilus parainfluenzae; Infective endocarditis; Mitral valve; Vegetation

Core tip: This review and illustrative case show a temporal change in the epidemiology of Haemophilus parainfluenzae (HPI) infective endocarditis in 2000–2022. Compared with a review of 26 HPI endocarditis cases from 1984–1995 by Darras-Joly et al, this review reported younger mean age, similar rate of infection in both genders, shorter time to diagnosis, higher association with intravenous drug use (IVDU), higher rate of embolic events in general, and tricuspid and pulmonic valve involvement. The rate of mitral valve involvement has remained steady over the past three decades, while there has been a decrease in the rate of aortic valve involvement. There has been a decrease in valvular vegetation rates and incidence of congestive heart failure as complications, while the mortality rate remained similar. These findings indicate improvement in diagnosis and treatment of HPI over the past three decades; however, they also suggest an increase in its virulence and an association with the rising rate of IVDU highlighted by the involvement of the right-sided heart valves.