Study authors say the consequences of misdiagnosing osteomyelitis can be severe in the disease setting of sickle cell disease (SCD).
Vaso-occlusive crisis is considered the most common manifestation of sickle cell disease (SCD), but a new case report offers a reminder that many of the symptoms of vaso-occlusive crisis can also occur in patients with osteomyelitis.
The case, reported in Clinical Case Reports, involved a 22-month-old female patient with type SS SCD who was taken to the hospital emergency department after experiencing left foot pain and swelling for 3 days. By the third day, the patient was refusing to ambulate. The patient had no fever and mild tachycardia, and both feet and toes were swollen and tender, although the left foot had more severe swelling, said the report’s co-authors.
After initial blood tests and x-rays, the patient was admitted for pain control for what appeared to be a vaso-occlusive pain crisis. However, the patient soon developed a high fever. Her blood culture was positive for gram negative bacilli at 25 hours, speciated as salmonella, the authors said.
“Inflammatory markers showed erythrocyte sedimentation rate of 23 mm/h andC-reactive protein of 35 mg/dL,” the authors reported. “The differential diagnosis was broadened to osteomyelitis versus septic joint versus bony abscess.”
After consultation with orthopedics and aspiration of fluid from the left ankle joint, the patient was given vancomycin in addition to her antimicrobial regimen. MRI showed osteomyelitis and several additional abscesses. The patient underwent irrigation and debridement of the plantar abscesses in her left ankle joint and left foot. Cultures collected intraoperatively grew pan-susceptible Salmonella species, the authors reported.
By her seventh day in the hospital, however, the patient had a worse fever and swelling in her right hand. She underwent positron emission tomography-CT, which was concerning for additional foci of osteomyelitis, the authors said.
Four days later, an MRI of her right hand and foot showed new multifocal sites, and an increased signal on her left foot led to a repeated incision and drainage.
It ultimately took 29 days in the hospital before the patient could be released. She took a 14-day course of ceftriaxone and then 6 weeks of amoxicillin. She completed the antibiotics without issue and had not had any recurrence at the time of the authors’ writing.
The authors noted that multifocal osteomyelitis is relatively uncommon in children. A previous study found about 1 in 4 children with SCD had multifocal osteomyelitis, while the rest had unifocal cases. They said accurate diagnosis is critical in children with SCD.
“Though uncommon, children with sickle cell disease are more prone to multifocal osteomyelitis, in which disease course and complications are typically much worse,” they wrote.
They noted that a previous case report detailed the case of a 2-year-old boy who developed sepsis and complications, including cardiopulmonary arrest and severe neurological damage.
The authors said radiographs are the best initial tool to use when osteomyelitis is a possibility.
“Typical findings are elevation of the periosteum, a well-circumscribed lucency denoting an abscess and soft tissue swelling,” they said. However, they cautioned that those findings could also be related to other health conditions, and they said patients with osteomyelitis might have normal plain radiographs for the first 10 days after symptom onset.
Bone scintigraphy can detect changes earlier in the course of infection, they said. The test has a high sensitivity rate, but a low specificity rate.
“If the bone has been violated, such as in a trauma or surgery, the specificity may be lower,” they said.
MRI, meanwhile, is more sensitive and specific, they said, and thus is the preferred diagnostic tool in cases of osteomyelitis.
“MRI does not use radiation but is just as sensitive, and more specific than bone scintigraphy,” they wrote. “On MRI, we also see complications such as abscesses and sinus tracts, making it more valuable than bone scintigraphy in such cases.”
They added that PET scans can be more efficient in whole-body imaging.
Still, they said there is no “gold standard diagnostic workup” for osteomyelitis, adding that erroneous diagnosis and missed diagnosis both can have serious implications for patients.
“Each case must be evaluated individually with focus on the history, the physical exam, the laboratory work-up, and imaging findings,” they wrote. “In patients with sickle cell disease, we must be more cognizant of the possibility of multifocal osteomyelitis.”
Scruggs M, Pateva I. Multifocal osteomyelitis in a child with sickle cell disease and review of the literature regarding best diagnostic approach. Clin Case Rep. Published online July 2, 2023. doi:10.1002/ccr3.7288