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
ARTICLE HIGHLIGHTS
Research background

Existing data indicate that the incidence of infective endocarditis (IE) continues to rise steadily. Although components of the skin flora including Staphylococcus spp., Streptococcus spp., and Enterococcus spp. are the most implicated organisms particularly in virulent IE, the oropharyngeal flora including the HACEK group of are a significant cause of IE.

Research motivation

An interesting presentation of Haemophilus parainfluenza (HPI) IE in a 25-year-old man with no significant past medical history and no predisposing risk factor for IE was the basis for this systematic review. It aimed to determine if there have been temporal changes in the presentation and prognosis of IE caused by HPI over the past two decades.

Research objectives

To characterize the risk factors, signs and symptoms, echocardiographic findings and the prognosis of IE caused HPI.

Research methods

A search of Medline, Pubmed, Scopus and Embase was conducted to identify the cases of HPI IE published in 2000–2022. A systematic review of these cases was performed to analyze the trends in the presentation and prognosis of HPI IE.

Research results

This systematic review of 39 HPI IE cases in the English literature highlights the slight male predominance of the disease, the nonspecific presentation with constitutional symptoms, the predilection for the mitral valve, a high rate of central nervous system embolic events and a lower mortality rate compared to IE caused by microbes of the skin flora.

Research conclusions

HPI IE is an indolent disease that requires a high index of suspicion to diagnose and is associated with a favorable prognosis with timely intervention.

Research perspectives

We have illustrated a case and conducted a two-decade systematic review of the HPI IE cases published in the English language literature. In doing so, we have highlighted its indolent course, presentation and prognosis. We have also compared our findings with those of a review of HPI IE cases between 1984 and 1995; in doing so, we have enumerated some temporal changes in this disease entity. These include a younger mean age of presentation, identical rate of infection between males and females, improvement in diagnosis, a higher rate of embolic events and an increasing association with intravenous drug use.