With Complex Cases Come Synergy and Serendipity: Diagnosing ROHHAD

David W. Cooke

Pediatric endocrinologist David W. Cooke

This article originally appeared in the Fall 2008 issue of Hopkins Children’s magazine.

The patient, a 3-year-old girl, had arrived in the middle of the night with elevated blood pressure and heart rate and what first-year resident Melanie Nies characterized as a “striking presentation.” The girl’s weight had suddenly shot up – 25 lbs. in one month – and she had been sleep walking and experiencing night terrors and a seizure.

Also, she had changed from an engaging little girl to an angry, withdrawn child obsessed with laying her clothes on her bed each morning. “It seemed almost ritualistic, and OCD (obsessive compulsive disorder) was one of the first diagnoses we entertained,” says Nies.

But pediatric endocrinologist and ward attending David Cooke zeroed in on the weight gain and considered Cushing’s Syndrome – caused by prolonged exposure to high levels of the hormone cortisol. Cooke didn't believe she had Cushings because it's rare in young children, but he had to show she didn't have it because of her Cushing’s-like symptoms of hypertension and weight gain. Initial salivary tests indicated high cortisol levels, but Cooke learned the parents had collected the saliva samples at 9 p.m. rather than midnight as specified, which tainted the results. A second round of tests showed normal levels.

Another disorder associated with problem behaviors and excessive eating, Prader-Willi Syndrome, was also considered but then discarded because the child lacked a history of neonatal hypotonia, or decreased muscle tone, and the characteristic small hands and feet associated with the syndrome.

Next, Cooke considered pheochromocytoma – a tumor of the adrenal gland – which would help explain the hypertension and increased heart rate. But like Cushing’s, the condition is very rare in 3-year-olds.

When blood tests showed elevated levels of metanephrine, Cooke started thinking neuroblastoma, an early childhood cancer that typically forms in the adrenal glands. Indeed, CT and MRI indicated there was a tumor near the spine, a site more typical for a neuroblastoma than a pheochromocytoma. Then serendipity played a hand when senior pediatric resident Hema Dave reviewed the literature and found an association between neuroblastomas and paraneoplastic syndrome – a rare degenerative disorder of unknown origins, though one hypothesis is that it may be an autoimmune reaction to a tumor. The syndrome’s symptoms include loss of muscle tone, sleep disturbances, and seizures, all of which the child had experienced.

Pieces of the puzzle were falling into place but Cooke and pediatric oncologist Ido Paz-Priel, also brought into the case, were still confounded by the rare constellation of symptoms and the findings. What would tie together the obesity, neuroblastoma, autoimmune and hyperdynamic problems?

Then serendipity played another hand during a case conference presented by endocrine fellow Stephen Djedjos on a similar case six months earlier, which fell under a rare syndrome called ROHHAD, or Rapid-Onset Obesity, Hypothalamic Dysfunction, Hypoventilation and Autonomic Dysregulation.

“I realized that ROHHAD and our case really have got to be the same thing,” says Cooke. “The overlap of findings is almost complete.”

By Gary Logan

NOTE: On Wednesday, Jan. 12, 2011, the TV show Mystery Diagnosis tells the story of Dr. Cooke's diagnosis of ROHHAD in a 3-year-old patient.