Haemophilus parainfluenzae endocarditis. Two cases and review of the literature in the past decade

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.

Haemophilus parainfluenzae Endocarditis Associated With Maxillary Sinusitis and Complicated by Cerebral Emboli in a Young Man

HACEK endocarditis is often difficult to diagnose given the slow-growing characteristics of the organisms involved. Haemophilus parainfluenzae, one of the HACEK organisms, is an uncommon cause of endocarditis. We describe a case of a previously healthy young man with H parainfluenzae endocarditis that was associated with maxillary sinusitis and severe systemic complications, including septic cerebral emboli and mitral valve perforation. Previously reported cases have also described a predilection for younger people, cardiac valve pathology, and a high prevalence of stroke.

Haemophilus parainfluenzae Mural Endocarditis: Case Report and Review of the Literature

Haemophilus parainfluenzae, which uncommonly causes endocarditis, has never been documented to cause mural involvement. A 62-year-old immunocompetent female without predisposing risk factors for endocarditis except for poor dentition presented with fever, emesis, and dysmetria. Echocardiography found a mass attached to the left ventricular wall with finger-like projections. Computed tomography showed evidence of embolic phenomena to the brain, kidneys, spleen, and colon. Cardiac MRI revealed involvement of the chordae tendineae of the anterior papillary muscles. Blood cultures grew Haemophilus parainfluenzae. The patient was treated successfully with ceftriaxone with resolution of symptoms, including neurologic deficits. After eleven days of antibiotics a worsening holosystolic murmur was discovered. Worsening mitral regurgitation on echocardiography was only found three weeks later. Nine weeks after presentation, intraoperative evaluation revealed chord rupture but no residual vegetation and mitral repair was performed. Four weeks after surgery, the patient was back to her baseline. This case illustrates the ability of Haemophilus parainfluenzae to form large mural vegetations with high propensity of embolization in otherwise normal cardiac tissue among patients with dental risk factors. It also underscores the importance of physical examination in establishing a diagnosis of endocarditis and monitoring for progression of disease.

Haemophilus parainfluenzae aortic prosthetic valve endocarditis (PVE) successfully treated with oral levofloxacin

Antibiotic treatment of native valve infective endocarditis (IE) traditionally consists of 4-6 weeks of intravenous (IV) antibiotic therapy. Oral (PO) antibiotic therapy is being used more frequently, for part or all of treatment for IE but experience in treating IE with PO antibiotics is limited. Preferable agents for oral therapy of IE are antibiotics with a high degree of activity against the IE pathogen and that have high bioavailability (>90%) so that achievable serum and tissue levels are the same as with equivalent IV antibiotics. Oral antibiotic therapy of IE has several advantages over IV therapy given the long duration of treatment, i.e., 4-6 weeks for IE. Firstly, outpatient oral therapy for IE is easily administered over 4-6 weeks and decreases hospital length of stay (LOS). Secondly, oral antibiotics (administered at the same dose, frequency and duration) costs much less than their IV counterparts. Thirdly, with PO therapy for IE there are no central venous catheter (CVC) associated complications, e.g., phlebitis, bacteremia, fungemia. Compared to native valve IE, prosthetic valve endocarditis (PVE), depending on the IE pathogen, requires prolonged therapy and usually valve replacement. Haemophilus sp. IE is relatively virulent and often complicated by heart failure and/or embolic phenomena. We describe the first reported case of Haemophilus parainfluenzae aortic PVE successfully treated with oral levofloxacin without aortic valve replacement.

Tricuspid valve endocarditis caused by Haemophilus parainfluenzae: a case report and review of the literature

Haemophilus parainfluenzae is a Gram-negative bacterium that is often difficult to isolate and identify. We report a rare case of tricuspid valve and pacemaker endocarditis caused by this organism and explore factors related to etiopathogenesis, prevention, and treatment.

Haemophilus parainfluenzae mitral prosthetic valve endocarditis in an intravenous drug abuser

Haemophilus species are an infrequent cause of subacute bacterial endocarditis. Of the Haemophilus species causing endocarditis, H. aphrophilus and H. parainfluenzae are more frequent causes of subacute bacterial endocarditis than H. influenzae. H. parainfluenzae requires growth factor V (nicotinamide adenine dinucleotide) and grows very slowly on routine culture media. H. parainfluenzae is a rare cause of "culture negative" endocarditis because it is a slow-growing organism. We present a case of a 42-year-old intravenous drug abuser with H. parainfluenzae mitral prosthetic valve endocarditis. To the best of our knowledge, this is the first case of mitral prosthetic valve endocarditis caused by H. parainfluenzae in an intravenous drug abuser.

Endocarditis caused by Haemophilus parainfluenzae identified by 16S ribosomal RNA sequencing

Haemophilus parainfluenzae, a human commensal, is an infrequent cause of serious disease. A case of endocarditis caused by this organism in a five year old boy with complex congenital heart disease is reported. The course of this disease was very aggressive, leading to heart failure, disseminated intravascular coagulation and multiorgan failure in spite of appropriate antibiotics and surgical intervention. The difficulties in the detection and identification of H parainfluenzae using conventional culture based technology, and the potential role of molecular techniques, are highlighted.

Crossed immunoelectrophoresis used for bacteriological diagnosis in patients with endocarditis

Sera from 151 patients suspected of having endocarditis were obtained during a period of 3 1/2 years at Rigshospitalet, Copenhagen. The sera were examined by crossed immunoelectrophoresis for antibodies to bacteria causing endocarditis. The patients were divided into four groups: 1. Patients with definite endocarditis, 2. Patients with culture-negative endocarditis, 3. Patients with uncertain endocarditis, and 4. Patients without endocarditis. In sera from patients suffering from endocarditis caused by viridans streptococci, precipitating antibodies were demonstrated by crossed immunoelectrophoresis (diagnostic specificity = 86%; diagnostic sensitivity = 100%) while other bacterial etiologies of endocarditis were less reliably demonstrated by this method.

Comparison of a new commercially prepared porphyrin test and the conventional satellite test for the identification of Haemophilus species that require the X factor

A test with a commercially developed porphyrin test agar was examined for the identification of Haemophilus spp. The porphyrin test agar method was compared with the conventional paper strip satellite method in tests with 187 isolates and was found to be easier to perform and interpret, giving a sensitivity of 98.7% and specificity of 94.7%.

Bacteremia caused by a beta-lactamase producing Haemophilus parainfluenzae strain of a new biotype. A case report

A case of Haemophilus parainfluenzae bacteremia without known infectious focus is reported. Phenotypically, the isolated strain is a typical H. parainfluenzae except for its ability to produce indole and beta-lactamase. Beta-lactamase producing H. parainfluenzae organisms are encountered occasionally, but to the best of our knowledge this is the first reported blood culture isolate with this ability. We propose a new biotype (IV) of H. parainfluenzae to accommodate strains that are indole, urease and ornithine decarboxylase positive.