Tricuspid valve endocarditis complicated by septic pulmonary embolism in an intravenous drug user

Abstract

Case reportA 32-year-old woman collapsed suddenly in the early hoursof the morning after visiting the toilet. Her partner made anemergency call immediately and started telephone-assistedcardiopulmonary resuscitation. Subsequent professionalresuscitation efforts were unsuccessful, and the woman waspronounced dead at the scene. She was known to be a long-term intravenous drug (IVD) user. A medicolegal autopsywas requested considering the woman’s young age and herspecific history of IVD abuse.Autopsy revealed the body of a poorly nourished Cau-casian woman, 162 cm in height and 55 kg in weight. Onexternal examination, there were prominent areas ofdepigmentation of the skin in the bilateral groin area, theanterior part of the right thigh, and the left cubital fossa.Fresh subcutaneous hemorrhages were seen on the anteriorpart of the right thigh with fresh puncture marks. Externalexamination also revealed multiple petechial hemorrhageson the right lower leg. Other external findings wereunremarkable.Dissection of the heart (weight, 280 g; dimensions13 9 10 9 4 cm) showed almost complete destruction ofthe anterior and septal cusps of the tricuspid valve (Fig. 1).The edges of the ulcerated cusps contained yellowishgranular vegetations. A smaller shaggy vegetation was alsopresent on the atrial aspect of the posterior cusp of thetricuspid valve, but the degree of destruction of the pos-terior cusp was not as severe as that of the anterior andseptal cusps. The leaflets of the tricuspid valve wereedematous and slightly coarse. A yellowish mass with aslightly granular surface was wedged into both branches ofthe pulmonary artery, causing complete obstruction(Fig. 2). The cardiac muscle was grossly normal. Therewas no septal defect. No pathological change was seen inthe coronary arteries.Further findings included septic changes of the spleen(weight, 460 g), congestion of the internal organs, and lungand brain edema.Histological examination of the lesions on the tricuspidvalve and the mass from the pulmonary artery revealed anorganizing thrombus with numerous colonies of bacteria,focal areas of acute inflammation, and microabscess forma-tion (Fig. 3a). Gram staining displayed gram-positive coc-cobacilli (Staphylococcus aureus). Histological examinationof the heart showed dispersed occlusions of small intramyo-cardial arteries bythrombicontaininglarge numbersofgram-positive bacteria with acute inflammation of adjacent areas ofmyocardium (Fig. 3b). There were no signs of nuclear atypiain the cardiomyocytes. Focal microabscesses containinggram-positive bacteria, karyorrhectic debris, and polymor-phonuclear cells surrounded small vessels in both lungs(Fig. 3c). Histologically proven focal and segmental septicglomerular infarcts were present in both kidneys (Fig. 3d).