31 January 2026
: Case report 
Cell-Free DNA Reveals Hidden Streptococcus anginosus in Cryptogenic Purulent Pericarditis in a Young Adult
Challenging differential diagnosis, Rare disease
Rafael Lessa Da Costa
ABDEF 1*, Natalia Viana Lopes Pereira BD 1, Ricardo Mendes Carneiro BD 1, Flavia Prado Fialho Santos BD 1, Julia Paulo Mourilhe Rocha BD 1, Flavio De Souza Afonso BD 1, Luciana Fazzio De Andrade BD 1, Paula Riedlinger Mont'Alverne Bordalo BD 1, Leticia Da Silva Alves BD 1, Pedro Castello Branco De Moraes BD 1, Gustavo Salgado Duque ABDF 1, Ricardo Mourilhe-Rocha ADEF 1
DOI: 10.12659/AJCR.951258
Am J Case Rep 2026; 27:e951258
Table 1 Analysis of pericardial fluid and peripheral blood.
| Examinations | Pericardial fluid | Blood |
|---|---|---|
| Coloring | Straw-colored | – |
| Leukocytes | 275/mm | – |
| Red blood cells | 140/mm | – |
| Polymorphonuclear | 214/mm | – |
| Mononuclear | 61/mm | – |
| Lactic dehydrogenase | 3472 U/L | 479 UI/L |
| Triglycerides | 57 mg/dL | – |
| Glucose | 4 mg/dL | – |
| Total proteins | 4.9 g/dL | 6.4 g/dL |
| Bacterioscopy | Numerous leukocytes | – |
| General cultures | Negatives | – |
| Xpert analysis for | Not detected | – |
| Cultures for mycobacteria, fungi, and yeast | Negative | – |