PEMPix is the American Academy of Pediatrics Section on Emergency Medicine’s visual diagnosis competition. It is held annually at the National Conference and Exhibition. This year, all ten finalists will be posted online on PEMBlog.com and at PEMPix.com, one a day with voting opening to AAP Section on Emergency Medicine members thereafter. I hope you enjoy this online-only format, and hope that it will serve to highlight some of the fantastic learning cases that our colleagues submitted this year. It was again very difficult for the panel of judges to select the finalists and I could not have done it without their assistance. As a special treat I’ve included a musical selection form the 1980s as an optional “hint,” and to serve as a soundtrack for your learning.

This PEMPix case was submitted by:

Ellie Souganidis, MD, Pediatric Emergency Medicine Fellow and Faria Pereira, MD from Texas Children’s Hospital

Dragging her along…

A 14-month-old female presents with right lower leg swelling and inability to bear weight on the right lower extremity. Over the past 1-2 weeks, the patient’s parents, daycare providers, and grandmother have noticed that the patient has been dragging her right leg when she cruises along the furniture or ambulates with her walker. On the day of presentation, the parents felt as though her right lower leg looked more swollen and her father felt a hard bump proximal to her right ankle, prompting them to go to the Emergency Department. No history of fever, rashes, or witnessed trauma to the area. She has had no surges, was a term infant, and her vaccines are up to date.

On exam she has normal muscle tone and moves all extremities well but refuses to bear weight on her right leg. The right lower extremity appears swollen compared to left lower extremity with a firm area of swelling along the distal medial aspect of the right lower leg. There is also a mild leg length discrepancy (RLE shorter than LLE). There is notably no redness or tenderness to palpation. Perfusion is normal. Plain radiographs were obtained.

What is the diagnosis?

A. Healing fractures

B. Osteosarcoma

C. Osteomyelitis

D. Enchondromatosis

E. Langerhans Cell Histiocytosis

D. Enchondromatosis

The right lower extremity radiographs demonstrated multiple enchondromas, consistent with enchondromatosis, more formally known as Ollier disease.

Ollier disease is a skeletal dysplasia characterized by the presence of multiple benign cartilaginous growths, known as enchondromas, which develop within the bones. The enchondromas are most commonly located in the long bones of the limbs near the growth plates. While these enchondromas may be present at birth, Ollier disease typically presents during the first decade of life with the development of palpable bony masses on the extremities and/or a limb length discrepancy secondary to asymmetric shortening of the leg both of which this patient had. Over time, bone shortening can result in abnormal shaping of the growing bone, affecting the surrounding muscles and joints. The affected bones are also more likely to fracture.

Ollier disease is estimated to occur in 1 in 100,000 individuals. All known cases have been sporadic. The majority of cases have been linked to a mutation in the isocitrate dehydrogenase 1 (IDH1) or isocitrate dehydrogenase 2 (IDH2) gene, although the pathogenesis of these enchondromas is still not understood. Malfucci Syndrome is often associated with Ollier disease, as this condition also consists of enchondromatosis with the added presence of hemangiomas and lymphangiomas.

Long-term management for patients with Ollier disease is primarily symptomatic and includes physical therapy and possible surgical correction of the affected limb if there is a significant limb length discrepancy or need for joint replacement. There is a 30% risk for malignant transformation of the enchondromas, most commonly into chondrosarcomas. Patients with Ollier disease are also at increased risk for ovarian and liver cancer.

Patient follow up

The patient followed up with Orthopedics, who ordered a skeletal survey and referred the patient to Genetics for further work-up. Skeletal survey demonstrated numerous additional enchondromas in her opposite leg and bilateral arms/hands.

In the Genetics clinic, she was noted to have some potentially evolving vascular lesions on the lower back and left lower extremity, raising the possibility of Maffucci Syndrome over Ollier disease. She continues to be followed by multiple subspecialists. Most importantly, she is meeting all of her developmental milestones including running and walking up stairs!

References

Silve C, Jüppner H. Ollier disease. Orphanet J Rare Dis. 2006(1):37. 2. Genetics Home Reference. (2020, May 26).

Ollier Disease. https://ghr.hlm.nih.gov/condition/ ollier-disease. Retrieved June 5, 2020.

National Organization of Rare Disorder. (2020). Ollier Disease. https://rarediseases.org/rare- diseases/ollier-disease/. Retrieved June 5, 2020

Amary MF, Damato S, Halai D et al. Ollier Disease and Maffucci Syndrome are Caused by Somatic Mosaic Mutations of IDH1 and IDH2. Nat Genet. 2011(12):1262-5.

Genetics Home Reference. (2020, May 26). Maffucci Syndrome. https://ghr.nlm.nih.gov/condition/maffucci-syndrome. Retrieved June 5, 2020.