What is the most likely diagnosis?

Cavitating mesenteric lymph node syndrome

Teaching points

– Cavitating mesenteric lymph node syndrome is associated with celiac disease

– It is characterized by the triad:
(a) low attenuation lymphadenopathies that may contain fat-fluid levels
(b) splenic atrophy
(c) villous atrophy

– Cavitating mesenteric lymph node syndrome is associated with poor prognosis

– Many patients die of complications of cachexia and intestinal hemorrhage. Patients are prone to sepsis, often due to infections commonly associated with clinical hyposplenism, such as pneumococcal infection

– Treatment: Correction of electrolyte abnormalities, strict gluten-free diet, steroid therapy

– In our case, US-guided biopsy of one of the mesenteric lymphadenopathies was performed. Histopathologic examination showed acellular, chylous fluid. It was negative for malignancy or mycobacterial infection. The diagnosis of cavitating mesenteric lymph node syndrome was made in the clinical setting of celiac disease

What is the next best step in the management?

Imaging-guided reduction
– avoids surgery
– absolute contraindications: perforation, peritonitis, hemodynamic instability
– pneumatic or hydrostatic – increases the intraluminal pressure in the colon
– under fluoroscopic or ultrasound guidance (US better because of the lack of ionizing radiation)

Hydrostatic reduction under ultrasound guidance was performed

Fluid-distended cecum with gaping ileocecal valve and reflux of fluid in the terminal ileum as a marker of successful reduction

Reference

Pušnik L, Slak P, Nikšić S, Winant AJ, Lee EY, Plut D. Ultrasound-guided hydrostatic reduction of intussusception: comparison of success rates between subspecialized pediatric radiologists and non-pediatric radiologists or radiology residents. Eur J Pediatr. 2023 Jul;182(7):3257-3264. doi: 10.1007/s00431-023-04987-1. Epub 2023 May 6. PMID: 37148276; PMCID: PMC10354123.

What is the most likely diagnosis?

Erdheim-Chester disease

Teaching points
– Erdheim-Chester disease (ECD) is a non-Langerhans cell histiocytosis characterized by multiorgan xanthomatous infiltration

– The diagnosis is based on clinical, imaging, and histopathological features

– Patients with ECD may present with bone pain, diabetes insipidus, exophthalmos, constitutional symptoms, interstitial lung disease, ureteral obstruction, renal impairment, cardiac dysfunction and tamponade, cerebellar or pyramidal symptoms, and xanthelasma.

– ECD has a wide range of manifestations throughout the body

– Skeletal involvement is the most common. At imaging, there is bilateral patchy or diffuse symmetric osteosclerosis of the lower extremity metaphyses and diaphyses, with relative sparing of the subchondral surfaces. Radiographically, cortical thickening, coarsened trabeculae, medullary sclerosis, and loss of the corticomedullary differentiation may be demonstrated

– Kidneys and retroperitoneum are often involved

– CT and MRI may show ‘hairy kidney sign’ that is demonstrated as irregular symmetric infiltration of the bilateral perirenal and posterior pararenal spaces

– Obstructive uropathy may result from medial displacement of the ureters

– Periaortic soft tissue is often shown, which is known as ‘coated aorta sign’

– Pulmonary involvement has been reported in 15-35% of patients with ECD and includes smooth interlobular septal thickening, micronodules, ground-glass opacities, thickening of interlobar fissures, and parenchymal consolidation

– Chest radiographs will often show interstitial edema pattern with cardiomegaly and pleural effusions that do not respond to diuretics 

– Orbital and central nervous system involvement are common findings. Retrobulbar masses that can cause proptosis and optic nerve edema may be present

– The hypothalamic-pituitary axis is the most common site affected within the central nervous system. Absence of the normal T1 hyperintense signal of the neurohypophysis occurs with enhancing nodular soft tissue of the pituitary stalk and posterior pituitary gland that results in central diabetes insipidus. Intra- and extra-axial cerebral and spinal lesions may be observed

– Treatment: Targeted therapy such as BRAF inhibitors, MEK inhibitors, interferon alfa, steroid therapy, radiotherapy, and surgery may be performed. There is no known cure for ECD and historically the prognosis has been poor 

– In our case, a biopsy from the perirenal soft tissue was performed. The histopathological findings confirmed the diagnosis of ECD