Undine-Syndrome: Really Only a Disease of Infants?

Introduction: The congenital central hypoventilation syndrome (CCHS) is a rare, hereditary disorder involving dysfunction of autonomous respiratory control. One of the causes of CCHS that has been described is a mutation of the PHOX2b gene. We report the case of a female patient first diagnosed as having a PHOX2b mutation at the age of 17 years.

Results/Case Description: Episode I: Several external presentations of a 17-year-old girl, who had been healthy up until then, with persistent headaches, paresthesia in the face, slurred speech and unsteady gait. Initial diagnosis: Ophthalmologist findings, electroencephalography (EEG), laboratory and cranial magnetic resonance imaging (c-MRT) were all normal. Slight improvement under intravenous analgesia was observed. Episode II: Persisting condition, admittance to a psychiatric clinic, and start of therapy with olanzapine and tavor were observed. During medication, hypoventilation with Pco₂ 80 mm Hg. Transfer to external pediatric intensive care unit, intubation, and start of antibiotic therapy for suspected pneumonia. CSF was normal, EEG with slow activity. Aciclovir therapy for suspected herpes infection was started. In the process, additional renal failure and transfer to our pediatric intensive care unit were observed. Initial examination: Paralysis of all the four extremities, maintained reflexes, and absence of spontaneous respiration were seen. Further diagnostic evaluation: The further diagnostic evaluation included MRT, electromyography, auditory-evoked potential, nerve conduction velocity, laboratory diagnostics, and LP. Oligoclonal bands were present in liquor. Administration of immunoglobulin and cortisone was observed. Improvement of condition with increasing spontaneous motor functions and spontaneous respiration was seen. Secondary findings of arterial hypertonia and corresponding therapy were seen. In the course, development of a psychotic disorder was also observed. Antibodies for autoimmune encephalitis were negative. End of antihypertensive therapy as suspected cause of psychosis. Subsequent clinical improvement was seen and the patient was discharged. Episode III: Readmission with further deterioration and CO₂ retention values up to 75 mm Hg. Noninvasive artificial respiration for suspected central hypoventilation syndrome was started, thereafter, leading to good CO₂ retention values and lasting clinical improvement. Verification of a PHOX2b mutation was done.

Conclusion: The PHOX2b mutation is one of the causes of the rare CCHS disorder. Although the disorder manifests itself shortly after birth in most cases, it should be borne in mind given elevated CO₂ retention values and conspicuous neurological symptoms irrespective of the patient age.