Appeal type: Medical necessity
Decision: Upheld

Diagnosis: Rhabdomyolysis
Treatment: Inpatient admission
The insurer denied the inpatient admission. The health plan's determination is upheld.

The patient is a male child with a medical history significant for an intestinal blockage at birth status post bowel resection that presented to the emergency department (ED) with several days of fever, nausea, vomiting, headache, and diarrhea. He was seen by his pediatrician and was diagnosed with a virus, new onset bilateral calf pain, and an inability to ambulate. He was drinking and voiding. He had not vomited for two days, and he had been afebrile for a day. His vital signs included a temperature of 37.4 degrees Celsius, a heart rate of 95 beats per minute (bpm), and a respiratory rate of 20 breaths per minute. The patient's examination was significant for no acute distress, a moist oral mucosa, a regular heart rate and rhythm, clear lungs, a soft non-tender abdomen, a decreased range of motion of his bilateral lower extremities due to pain, an inability to bear weight, and calf muscle tenderness to palpation. Laboratory testing was positive for influenza B, a creatine kinase (CK) of 744, a white blood cell count (WBC) of 3.1 thousand (K), and platelets of 178K. He was diagnosed with rhabdomyolysis secondary to influenza B infection. He was started on intravenous (IV) fluids and was admitted for ongoing management.

Admission orders included continued hydration and serial laboratory studies. The patient's CK increased and peaked at 10,899; with increased fluids, the CK level decreased to 6,972 at discharge. His appetite improved, and he was able to stand at first and then walk independently. Once his activity had returned to normal, he was deemed stable for discharge.

At issue is the medical necessity of an inpatient admission.
I uphold the health plan's determination, in whole.

The inpatient admission was not medically necessary.

Rhabdomyolysis is generally defined as an elevation of serum creatine kinase activity at least ten times the upper limit of normal, followed by rapid decrease to normal. It occurs when skeletal muscle is broken down, releasing electrolytes and myoglobin into the circulation. Rhabdomyolysis may be caused by substance abuse, medications, trauma, or seizures. It may also be virus-associated, with the most common virus being influenza. Clinical findings include myalgia, weakness, and pigmenturia, but less than 10 percent (%) of patients present with this triad. The most concerning complication is acute kidney injury, although arrhythmias from electrolyte abnormalities also are a source of morbidity. Acute renal failure may occur as a result of acute tubular necrosis when myoglobin causes obstruction in the kidney. This typically occurs with CK (creatine phosphokinase (CPK)) levels greater than 16,000. Initial treatment is aimed at preserving renal function, managing electrolyte derangements, and aggressively maintaining hydration.

Myalgia is a typical complaint for patients with influenza, but acute myositis and rhabdomyolysis occur as well, more often in children than in adults. Treatment of rhabdomyolysis in this circumstance is aimed at preventing acute renal failure.

This young child presented with a several day history of flu-like symptoms and a new-onset of bilateral leg pain with an inability to ambulate. Testing was positive for influenza B. Creatine kinase was elevated. He was treated with IV fluids in the ED. He was admitted for further management with peaking CK over 10K. He symptomatically improved over the course of his hospital stay with decreasing CK. While it was reasonable to monitor him in the hospital while providing IV fluid hydration, he was overall hemodynamically stable with no evidence of renal failure and adequate fluid intake. He did not require an acute inpatient admission and could have been safely managed at a lower level of care.