Infective Endocarditis Caused by Streptococcus Alactolyticus and Kocuria Kristinae Complicated with Severe Thrombocytopenia: A Rare Case

1Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia 2Faculty of Medicine, Duta Wacana Christian University, Yogyakarta, Indonesia 3Department of Cardiology and Vascular Medicine, Dr. Soetomo General Hospital, Surabaya, Indonesia SAŽETAK: Uvod: Infektivni endokarditis (IE) fokalna je infekcija uzrokovana bakterijskim, virusnim ili gljivičnim mikroorganizmima, koja unutar srca zahvaća endokard i zalistke. Streptococcus alactolyticus, klasificiran po IV DNA klasterom S. bovis / S. equinus kompleksa, bakterija je koja se rijetko nalazi u izolatu te koja malokad uzrokuje IE u ljudi. Kocuria kristinae je gram-pozitivna bakterija. Dosad je objavljeno samo šest slučajeva IE-a uzrokovanih infekcijom bakterijom K. kristinae. Trombocitopenija i disfunkcija trombocita mogu se pojaviti u IE-u te su povezani s kliničkim ishodom. Postoje različite hipoteze o mehanizmima kojima se objašnjava trombocitopenija u IE-u. Prikaz slučaja: Predstavljamo slučaj dvadesetpetogodišnje bolesnice koja se žalila na palpitacije dva tjedna prije primitka u bolnicu. Prvi je simptom bila povišena temperatura šest mjeseci prije primitka. Hemokulture su utvrdile S. alactolyticus i K. kristinae. Ehokardiografskom su pretragom pronađene vegetacije na anteriornom i posteriornom listiću mitralnog zalistka uz tešku mitralnu regurgitaciju. Bolesnica je tijekom hospitalizacije imala tešku trombocitopeniju bez znakova krvarenja. Šesnaestog dana hospitalizacije naglo se počela žaliti na abdominalnu bol i zaduhu. Bolesnica je umrla, a uzrok smrti bili su septički emboli. Zaključak: Prikazan je slučaj IE-a uzrokovana rijetkim bakterijskim patogenima (S. alactolyticus i K. kristinae) koji je pogoršala trombocitopenija. Liječenje IE-a s trombocitopenijom zahtijeva oprez jer je to stanje povezano s lošim ishodima. U ovom se slučaju loši ishodi mogu povezati s trombocitopenijom uz prisutnost specifične bakterije, S. alactolyticus, koja je poznata kao bakterija koja često uzrokuje septičku emboliju. SUMMARY: Introduction: Infective endocarditis (IE) is a focus infection caused by bacterial, viral, or fungal microorganisms within the heart that involves the endocardium and heart valves. Streptococcus alactolyticus, classified under DNA cluster IV of the S. bovis/S. equinus complex, is a sparse isolated bacterium that rarely cause IE in humans. Kocuria kristinae is a gram-positive bacteria. Until now, there have been only six IE cases caused by K. kristinae infections reported in the literature. Thrombocytopenia and platelet dysfunction can manifest in IE cases and are related to the clinical outcome. Different mechanisms have been hypothesized to explain thrombocytopenia in IE. Case report: We report the case of a 25-year-old female patient who complained of palpitation two weeks before admission. Initially, the patient complained of fever arising six months before admission. Blood cultures showed S. alactolyticus and K. kristinae. Echocardiography examination showed vegetation on anterior and posterior mitral valves with severe mitral regurgitation. During hospitalization, the patient also suffered from severe thrombocytopenia without bleeding signs. On day 16 after hospitalization, the patient suddenly complained of abdominal pain and dyspnea. The patient was declared deceased with cause of death due to septic emboli. Conclusion: We reported a case of IE caused by rare bacterial pathogens, S. alactolyticus and K. kristinae, which were aggravated by thrombocytopenia. Management of IE with thrombocytopenia requires caution because it is associated with poor outcomes. In this case, poor outcomes can be connected to thrombocytopenia coupled with the presence of specific bacteria, S. alactolyticus, which is known as a bacterium that often causes septic embolism. KLJUČNE RIJEČI: infektivni endokarditis, valvularna bolest, Streptococcus alactolyticus, Kocuria kristinae, trombocitopenija. KEYWORdS: infective endocarditis, valve disease, Streptococcus alactolyticus, Kocuria kristinae, thrombo cytopenia. CITATION: Cardiol Croat. 2021;16(7-8):246-51. | https://doi.org/10.15836/ccar2021.246 *AddRESS fOR CORRESpONdENCE: Andrianto, Department of Cardiology and Vascular Medicine, Faculty of Medicine, Universitas Airlangga Dr. Soetomo General Hospital, Surabaya Jl. Mayjen Prof. Dr. Moestopo No.6-8, Surabaya 60286, Indonesia. / Phone: +62 812 3300 0705 / E-mail: andrianto@fk.unair.ac.id ORCId: Ivana Purnama Dewi, https://orcid.org/0000-0002-1602-3384 • Ismail Damanik, https://orcid.org/0000-0003-1473-3355 Kristin Purnama Dewi, https://orcid.org/0000-0001-9328-6690 • Muhammad Yogiarto, https://orcid.org/0000-0003-4372-6875 Andrianto, https://orcid.org/0000-0001-7834-344X