1. Abstract We report a case of infective end ocarditisinapatient with congenitalheartval velesions accompanied by Strept ococcusgordonii in fection. A61-year-old manpresented with recurrent fever for four months. Immune system and myelopoietic disorders and tuber culosis were all ruled out as possible causes of the fever.He was diagnosed with subacute Infective end ocarditis (IE) after bloodcul ture analysis, which revealedpre sence of a Gram-negativebacterium - Streptococcus gordonii,
2. Introduction Infectiveendocarditis(IE)isalife-threateningcardiovasculardisease with an annual incidence of 1.5/100,000-15/100,000 and a mortality rate of 20%-25% [1]. The disease is caused by a pathogenic microorganism that directly infects heart valves, the endocardiumoftheventricularwallortheendocardiumoftheadjacent aortaviathebloodstream,oftenleadingtosuperfluousorganisms [2]SubacuteIEischaracterizedbyaninsidiousandslowon- set, with a long course that usually lasts between 6 weeks and 3 months.The patient mostly experiences cardiac problems. Due to theinsidioussiteofinfection,Notably,theIEpatientshavediverse andnon-specificclinicalmanifestations,whichsubsequentlylead tomisseddiagnosisandmisdiagnosisthatresultinseriousadverse consequencesthatthreatenthequalityof life[3].Therefore,early diagnosis coupled with timely treatment are crucial for management of the disease. In the present study, we report a case of IE causedbyStreptococcusgordonii,withfeverasthemainmanifestation, at our hospital.
3. Case Report A61-year-oldmanpresentedatourhospitalwithintermittentfever and malaise for 4 months. Four months before the visit, he had developed a fever (up to 40℃), mostly in the afternoon and at night,accompaniedbychills,andmalaise.Althoughhisbodytemperaturenormalizedafterthreedaysofanti-infectiontreatmentvia self-infusion, a the fever reappeared after stopping the treatment. Thediseaseworsenedprogressively,hisbloodpressuredecreased andwasaccompaniedbyincreasedheartrate.Thepatientwasdiagnosedwithinfectiousshockandsubsequentlytransferredtoour hospital for further treatment. Physical examination revealed a slightly pale skin and mucous membranes, with no anger in the jugular vein, and enlargementof the cardiacborder to the left.There wasalso evidenceof grade IIIIVdiastolicmurmurintheaorticvalvearea,andperipheral vascular signs (+). Laboratory test results revealed normal leukocytesandneutrophils,C-reactiveproteinandcalcitoninlevelsof 53.1 mg/l and 2.66 ng/ml, respectively, as well as liver and re-nal function that were within normal limits. PPD test results were negative, paired blood cultures (asymmetric limbs, e.g., left upper limb and right lower limb) on three consecutive days shows Gram-positivecocci.MacrogenetictestGNSshowsStreptococcus gordonii.CardiacultrasonographyshowsEF52%andaorticvalve leaflet thickening and echogenic enhancement, moderate regurgitant signal under the aortic valve in diastole, small amount of regurgitantsignalontheleftatrialsideofthemitralvalveinsystole, small amount of regurgitant signal on the right atrial side of the tricuspid valve in systole, ascending aortic internal diameter 46 mm, aortic valveVmax 2.2 m/s, enlarged left atrium, aortic valve calcificationandmoderateregurgitation,mildregurgitationofthe second and tricuspid valves (Figure1, 2); Cardiac MRI results were consistent with dilated cardiomyopathy changes, left heart insufficiency, significantly reduced systolic function, aortic valve thickening and stenosis, incomplete closure, mitral valve, tricuspidvalveincompleteclosure,smallamountofpericardialeffusion, pericardialinflammatorychanges,andasmallamountofbilateral pleural effusion. Figure1:Bidirectionalregurgitationofthe aorticvalve(shownby arrows). Figure2:Aortic valvebulge (shownin circle) Bone marrow aspiration: Flow cytometry showed an increase in the proportion of granulocytes and nucleated red, and a mild decrease in the proportion of lymphocytes. The phenotype was not abnormal.Abnormal immunoglobulins and identification of multiple myeloma: Immunofixation electrophoresis (IFE) results: serum:polyclonalimmunoglobulins,no“Mprotein”detected;urine: no kap and lam light chain “M protein” detected. Serum protein and immunofixation electrophoresis revealed no significant “M protein”, a reduction in albumin levels, and elevated levels of α1 andγglobulin.SerumIgG,IgA,IgMandkap,aswellaslamlight chain levels were normal, with high IgE levels. We also found a moderate increase in the level of urine kap light chain and 24- hoururineproteinlevels.Proteinelectrophoresisrevealednospe- cific band in urine. No light chain type “M protein” was detected in urine via immunofixation electrophoresis, while bone marrow aspiration revealed normal results. The results excluded multiple myeloma. Table 1. The patient’s prolonged unexplained fever, coupled with blood culture and echocardiographic results made us to strongly suspect subacute infective. The patient’s fever had subsided after 9 days of continuous treatment, and his infection index was under control.Consequently,aorticvalvereplacementwasrecommend- ed following anti-infection treatment. Preoperative sudden onset of chest and abdominal pain with profuse sweating, Emergency transesophagealultrasonography.ResultsarepresentedinFigure 3.Summarily,wefoundevidenceofaorticvalveredundancywith perforation, while emergency CTAresults revealed moderate stenosis of the lumen at the beginning of the abdominal trunk. The possibilityofbacteriophagealinvolvementandvisiblepenetrating ulcers was considered (Figure 4). Consequently, the surgical approachwaschangedfromsimpleaorticvalvereplacementtoAor- tic valve replacement surgery and aortic valvuloplasty. Intraoperative examination revealed the following results: moderate levels ofayellowishpericardialfluid,markedwideningoftheascending aorta, marked malformation of the aortic bicuspid valve, leaflet destruction with perforation and massive regurgitation, complete leafletremoval,placementofaorticvalvebioprosthesis,andcompression of the artificial vessel to wrap the ascending aorta. The operationwassuccessfullycompleted.Postoperativepathological analysisrevealedfibrousconnectivetissuehyperplasiawithfocal glassyandmucinousdegeneration,localizedfibrindeposition,and evidenceofcalcifiedfociinthevalvetissue.Thepatientreceived antiinfection treatment for one month after surgery. Reexaminationrevealedthathisliver,kidneyandcardiacfunctionshadbeen restored back to normal.
4. Discussion In 2016, the American association for thoracic surgery (AATS) published an expert consensus on surgical management of infective endocarditis, the most recent guiding document for management of this condition.AATS expert consensus indicates that, the current DUKE criteria, which are based on diagnostic criteria proposed in 1994 and have subsequently been modified several times, are the most practical for the diagnosis of IE [4].The most common clinical IE manifestation is fever, with insidious onsetin subacute cases and relatively mild toxic symptoms that may range from weeks to months.Although IE is a common cause of unexplainedfever,only18.6%-20.3%ofpatientspresentwithtyp- ical manifestations described in the DUKE criteria, such as skin petechiae, emboli, splenomegaly, and Osler nodules.About 30% of IE patients do not exhibit obvious heart murmur during early stagesofdiseasedevelopment,andduringthecourseoftreatment. The doctors who treated the patient in the present study, beforehecametoourhospital,thoughtthattheheartmurmurcouldbe explained by mitral regurgitation and did not consider the possibilityof IE. Notably, theywere satisfied with improvementof his clinicalsymptomsanddidnotfollowupthediseasechange,aphenomenon that resulted in a delay of the disease. Bacteremia, caused by pathogenic microorganisms in the blood,is the basis for the development of IE. Blood culture tests have diagnostic value and can help guide selection of anti-infective drugs. The main pathogens and major routes of infection in IE havechangedinrecentyears.Notably,virulentanddrug-resistant staphylococciarethemostcommonfactors,andaremorelikelyto occur in elderly patients, as well as those with nosocomial chronic disease and intracardiac implants. In the present study, blood culture results suggested that this patient had Streptococcus gordonii infection.This pathogen belongs to the Gram-stain-positive retardedstreptococcalgroupandisapartlyanaerobicα-hemolytic streptococcus (VGS). Recent studies have shown that Community-acquired autologous valvular endocarditis caused by VGS is alsocommoninIEpatients,particularlyindevelopingcountries [5],andmanyofthemarecausedbyStreptococcusgordonii.Generally, S. gordonii colonizes the oral cavity and upper respiratory tract,Mainlyinvolvedinthecompositionofdentalplaque,itis a conditional pathogen, usually not pathogenic. In recent years, many cases of S. gordonii infections have been reported in China andabroad,includingsepsis,IE,splenicabscessandsepticarthritis.Theseinfectionshavesubsequentlybeenassociatedwithpoor oralhygiene,looseteeth,dentalsurgeryandotherinvasiveprocedures.Thepatientinthepresentstudyexhibitedupperrespiratory tract infection symptoms, such as a sore and dry throat 1 week before onset of fever. However, he did not pay attention to these symptoms and had overexertion during the same period [6]. It is worthnotingthatmedicalhistoryisimperativetoeffectivedisease diagnosis. Echocardiographyis a key procedurefor confirmingIE diagnosis [7], due to the fact that it cannot only detect the superfluous organisms at an early stage, but also accurately measure their sizes, thereby facilitating assessment of disease severity, understanding cardiac function, and detection of cardiac complications, among others[8].However,echocardiographyisinfluencedbysubjective factors.Inthepresentcase,initialcardiacechocardiographyfailed to detect superfluous organisms in this patient’s heart valve, and Relaxed vigilance. We attributed this to the fact that the location and size of the flab were not easily detectable by the ultrasound beam,andphysicianinexperience.Transesophagealechocardiographycandetecttheredundantorganismswithadiameterof1-1.5 mmanddirectlyrevealtherelationshipbetweentheredundantorganisms and the valve from the posterior left atrium, achieving a positive detection rate of up to 90%. However, echocardiography is not an ideal detection tool for patients with severe valvular lesions, bulging valves < 2 mm, prolapsed valves, or valves without bulgingvalves/Basedonthis,anegativeresultdoesnotcomplete- ly exclude IE. SuccessfulIEtreatmentdependsonefficientremovalofpathogenicmicroorganisms,andsurgeryhasshownpromiseinsuccessfully eradicatingthem[9].Previousstudieshaveshownthatinorderto reducemorbidityandmortality,20-50%ofpatientsrequiresexual cardiac surgery to remove infected tissue and restore valve function [10-12]. In fact, timely surgery is the only hope for saving a patient’slifeinacaseofsevereIE.Internalmedicineandsurgery havetheirownadvantagesandshortcomingsduringIEtreatment. Althoughinternalmedicine-basedtreatmentcanclearmostofthe microorganisms, it was not efficacious in the patient in this case. Useofanti-infectiontreatmentnotonlycausedanimpairment of his cardiac function, but also resulted in hemodynamic abnormalities due to the destruction of intracardiac structures, and the emergenceofbacterialembolidislodged.Therefore,internalmedicine treatment alone cannot prevent occurrence of superfluous events, necessitating application of surgical treatment which correctscongenitalvalvemalformation,andrestoresheartvalve.The patient in the current study was subjected to surgical treatment, whichcorrectedhiscongenitalvalvemalformation,restoredheart valvefunction,andimprovedheartfailure.Thepatientrecovered. Choosingtherighttimeforsurgeryisthekeytoeffectivesurgical treatment.Itisgenerallybelievedthatpatientswithheartfailureor hemodynamic disorders, persistent infections, uncontrolled intracardiaclocalinfections,refractorymicrobialinfections,persistent flabbybiology>10mmwithembolismorvalvedysfunctionshould be operated as soon as possible [13]. Echocardiography results of thepatientinthepresentstudyrevealedaflabbybiologymeasuring 1.2cm * 1.2 cm, with indications for surgery. There are also conservativeswhobelievethatsurgicalinterventionisnotappropriate in the acute phase, due to a possibility of increased occurrence of complications and high surgical risks. Notably, controversy still surroundsthetimingandindicationsforsurgerynecessitatingfurtherresearchexplorationswithlargerandomizedcontrolledclinicaltrials.Althoughapplicationofcardiacsurgeryfortreatmentof activeinfectiveendocarditisisonlyacenturyold,recentadvances in surgical techniques and perioperative management have made it the cornerstone of IE treatment. Moreover, there is no uniform standard for indication, timing, and risk assessment of surgery in activeIE,duetothecomplexityandvariablenatureofthedisease [14].Therefore,clinicaldecisionmakingincomplexcasesmustbe fullyindividualized,takingintoaccountthepatient’sdemographic characteristics,comorbidities,diseaseseverity,andstage,inorder to determine whether and when to perform surgical intervention andtopreparefortheforeseeablerisksaftersurgery.Thereisneed to consult hospitals with multidisciplinary teams specializing in IEincasesofcomplexIEcases.GiventhelargenumberofIEpatientsinChina,thereisaneedforconcertedeffortsacrossclinical research to standardize IE treatment strategies by focusing on the unresolved international issues. Since the population and pathogenic spectrum of IE patients in China are different from those in Europe and the United States, there is need to develop active IE surgery strategies for the Chinese population.
5. Conclusion Thefollowingconclusionsaredrawnfromthepresentcasestudy: 1. Infective endocarditis is characterized by insidious onset, difficult diagnosis, aggressive condition and susceptibility to flabby dislodgement events. Therefore, patients with recurrent fever of unknown origin need to be alert. 2. ThereisneedforclinicianstoraiseawarenessonIE,especially byperformingcomprehensivephysicalexaminationsandanalysis. Clinicians should highly consider IE in patients with unexplained fever,especiallythosewithunderlyingcardiacdiseaseconditions. 3. PatientswithhighsuspicionofIEbutnegativeechocardiogram should be retested or operated by a senior ultrasonographer. In caseswheretransthoracicechocardiogramsuggestsindirecthints, suchasvalveprolapse,incompleteclosure,orsepticlesions,trans- esophagealechocardiogramshouldbeperformedpromptlytoimprove the detection rate. 4. Disease course in patients with active IE is often complex and variable.AlthoughinternationalguidelineshavesomewhatstandardizedtheindicationsandtimingofsurgeryinactiveIEpatients, thereisstillaneedforconcertedeffortsfromanIE-specificmultidisciplinary team during decision making for specific patients. In fact, the discussion on the indication and timing of surgery is a gameofriskversusexpectedbenefit.Therefore,assessmentofthe riskofsurgeryinactiveIEpatientsisimperativetoeffectivemanagement of the disease.
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Yifan Qu. A Valve Repair after Infective Endocarditis Secondary to Perforation Causedby Streptococcus Gordonii -ACase Report and Literature Review. Annals of Clinical and Medical Case Reports 2022