Overwhelming pneumococcal bacteremia revealed by a peripheral blood smear in a 74-year-old healthy woman

Fulminant Streptococcus suis infection detected on peripheral blood smear: A case report

Streptococcus suis, a gram-positive coccus, is recognized as an emerging zoonotic pathogen that causes serious infections in humans, such as bacterial meningitis and sepsis, with poor outcomes. The pathogen is known to be transmitted through the consumption of raw pork or occupational exposure to pigs. A previously healthy 38-year-old woman with occupational exposure to raw pork was presented to our emergency department with a clinical diagnosis of rapidly progressive septic shock. Peripheral blood smears detected chains of cocci inside granulocytes, which led to the early recognition of gram-positive cocci in short chains before the blood culture test results. Blood cultures later tested positive for S. suis serotype 2. The patient's condition deteriorated despite aggressive resuscitative measures including antibiotics, vasopressors, multiple blood transfusions, mechanical ventilation, and renal replacement therapy. Initiation of veno-arterial extracorporeal membrane oxygenation was ineffective, and the patient died 16 h after admission. The identification of bacteria in the peripheral blood smear indicated an overwhelming infection and led to the rapid recognition of bacteremia. Our report aims to raise awareness about fatal zoonotic pathogens and to promote the unique role of peripheral blood smears that could provide preliminary diagnostic information before blood culture results.

Fulminant pneumococcal infection

Fulminant pneumococcal infection is a fatal pneumococcal infection that tends to occur in immunocompromised hosts, such as patients who are asplenic or on immunosuppressant therapy. We experienced a case of a 73-year-old Japanese man with a medical history of coronary stent implantation and catheter ablation for atrial flutter who presented with dyspnoea at rest. The patient was diagnosed with streptococcal pneumonia based on a urine antigen test and CT. Despite the use of effective antibiotics and systemic therapies, his clinical course was rapidly progressive and he died 18 h after admission. This case of fulminant pneumococcal infection is reported along with the autopsy findings.

Pneumococcal vertebral osteomyelitis and psoas abscess in a patient with systemic lupus erythematosus disclosing positivity of pneumococcal urinary antigen assay

A 53-year-old woman with systemic lupus erythematosus presented with a 3-day history of fever and coughing. Diagnosis of pneumococcal bronchitis was made based on symptoms and positivity of pneumococcal urinary antigen test. On day 3, severe low back pain acutely occurred. Pneumococcal vertebral osteomyelitis and psoas abscess was diagnosed 17 days later by yield of penicillin-susceptible S. pneumoniae strain in blood cultures and drainage fluid. Although pneumococcal urinary antigen test is a useful tool for the diagnosis of pneumococcal pneumonia, we should consider the possibility of pneumococcal infections other than pneumonia or overwhelming bacteremia in immunosuppressive patients when urinary antigen test is positive.