CincyKidsRad

Cincinnati Children's Radiology

Gonococcal Septic Arthritis

Sagittal T2 (image 1), sagittal T1 postcontrast (image 2), and axial T1 post contrast (images 3 and 4) gonococcal arthritis show a large joint effusion (arrow) with thickened, enhancing synovium, muscular enhancement with a focal area that does not enhance (dashed arrow), and fascial thickening and enhancement (arrowhead). Gonococcal arthritis occurs from the hematogenous spread of neisseria gonorrhea. Compared to nongonococcal causes of septic arthritis, gonococcal arthritis is more likely to be polyarticular and have a negative culture.

Image Summary

• A1 - Moderate joint effusion.
  The most common disorders associated with abrupt effusion in an adolescent or child are patellar dislocation / relocation, cruciate injury, or juvenile idiopathic arthritis (JIA). However, when these are not present, you should expand the search pattern. In this case, note the green arrows on images 4, 5, and 6. The arrows indicate the same focal cartilage defect in the sagittal, coronal, and axial perspectives.

• Axial FLAIR (image 1) and sagittal T1 FLAIR MRI images show a hypothalamic hamartoma (arrow). Patients with these lesions classically present with gelastic or laughing seizures. Hypothalamic hamartomas may also cause symptoms such as precocious puberty or behavioral and cognitive difficulties. On imaging, hypothalamic hamartomas are isointense to gray matter on T1-weighted images and hyperintense on T2-weighted images, without enhancement after contrast administration.

• Coronal (image 1) and sagittal (image 2) T1-weighted images focused on the pituitary show a thickened proximal infundibulum (arrow) with increased signal and narrowing distally. Langerhans' cell histiocytosis can rarely affect the central nervous system. When the central nervous system is affected, it most commonly appears as thickening of the infundibulum. Patients may present with diabetes insipidus.

• Sagittal T2 (image 1), sagittal T1 post contrast (image 2), axial FLAIR (image 3), and axial T1 post contrast (image 4) MRI images and child with diffuse leptomeningeal glialneuronal tumor shows lobular abnormal signal (arrows) extending from the ependymal surface of the ventricular system into the surrounding parenchyma. There is only minimal enhancement of the tumor. Diffuse leptomeningeal glial neuronal tumor is a rare neoplasm that most commonly occurs in boys. Characteristically, the tumor appears with diffuse leptomeningeal thickening. Multifocal cystic lesions may appear in both the brain and spinal cord.

"A 52-year-old man presented with a 20-minute history of chest pain radiating to the left shoulder and neck, associated with dyspnea and diaphoresis. He had a history of hypertension, long-term smoking, and a sedentary lifestyle. On physical examination, bibasilar crackles were noted on lung auscultation. An electrocardiogram (ECG) was performed in the primary care setting, and the patient was promptly referred to the emergency department."

"A 28-year-old woman presented with a 3-day history of intense pruritus over the lower back. She reported no recent travel or exposure to new environments. She cares for a small kennel with approximately eight dogs rescued from the streets. Physical examination revealed multiple small vesicles, some clustered and others scattered, predominantly involving the lumbar region and the left gluteal area."

"A 4-month-old male infant presented with skin lesions localized to the chin for the past 3 days. Physical examination revealed multiple small pustules with surrounding inflammatory signs on the chin, along with a few scattered papules on the chest."

"Patient in late teens presenting after a collapse, no chest pain, no previous cardiac history, no history of sudden death in family. Are there any features in this EKG that would warrant further work-up or is this just a pediatric EKG?"