A 21-Year-Old Immunocompetent Man With Hemoptysis and Rash.

CASE PRESENTATION: A 21-year-old man presented to the ED of The George Washington University Hospital complaining of chills, shortness of breath, hemoptysis, and a generalized rash. Three days before admission, he noticed a productive cough, severe sore throat, and subjective fever. He also experienced extreme fatigue, generalized sweating, and chest pain with coughing. On the day before admission, he experienced a nonpruritic rash on his neck, palms, and dorsal surfaces of his feet and sputum with streaks of blood. The patient had no significant medical or family history. He had no sick contacts, and his only recent travel was to an outdoor concert in a woody area of the northeastern United States about a month earlier. He did not report recent contact with birds or visits to caves. He is single, lives alone in an apartment, and consumes about 4 alcoholic beverages a week. Occasionally, he smokes cannabis and e-cigarettes. He is sexually active with men, and his last unprotected sexual encounter was a month earlier. He denied photophobia, rhinorrhea, ear pain, nasal congestion, abdominal pain, nausea, vomiting, diarrhea, or dysuria.

Pediatric Coronal Suture Fiber Alignment and the Effect of Interdigitation on Coronal Suture Mechanical Properties.

The morphological and mechanical properties of the pediatric skull are important in understanding pediatric head injury biomechanics. Although previous studies have analyzed the morphology of cranial sutures, none has done so in pediatric specimens nor have previous studies related the morphology to mechanical properties of human sutures. This study quantified the geometry of pediatric cranial sutures and investigated its correlation with the suture mechanical properties. First, the suture fiber alignment was quantified using histological analysis for four ages-neonate, 9 months-old, 11 months-old, and 18 months-old. For the morphometric investigation of the suture interdigitation, suture samples from a 6-year-old were scanned using micro-CT and the level of interdigitation was measured using two techniques. The first technique, the sinuosity index, was calculated by dividing the suture path along the surface of the skull by the suture distance from beginning to end. The second technique, the surface area interdigitation index, was calculated by measuring the surface area of the bone interface outlining the suture and dividing it by the cross-sectional area of the bone. The mechanical properties were obtained using methods reported in Davis et al.6. The results of the histological analysis showed a significant increase in fiber alignment in older specimen; where random fiber alignment has an average angle deviation of 45°, neonatal suture fibers have an average deviation of 32.2° and the 18-month-old fibers had an average deviation of 16.2° (p < 0.0001). For the suture index measurements, only the sinuosity was positively correlated with the ultimate strain (R (2) = 0.62, Bonferroni corrected p = 0.011) but no other measurements showed a significant relationship, including the amount of interdigitation and elastic modulus. Our results demonstrate that there is a distinct developmental progression of the suture fiber alignment at a young age, but the differences in suture interdigitation can only predict the ultimate strain and no other mechanical properties.