Table 2 Summary of clinical studies of a patient with a KCC3 T991A mutation.
TestResult
EMG*Abnormal: Motor > sensory
axonal neuropathy
MRI brainNormal
MR spectroscopy brainNormal
Serum electrolytesNormal (except low creatinine)
Urine electrolytes§Normal
HearingNormal in speech and pure tones
and normal tympanometry and
auditory brainstem response
Osmotic fragilityNormal erythrocyte osmotic fragility
Peripheral blood smearNo acanthocytes and normal smear
Creatine kinaseNormal (136)

*See Table 1 for specific nerve conduction study data and interpretation.

†See Fig. 1 for picture of normal MRI brain including normal brain volume and corpus callosum.

‡Specific values are as follows: Na, 138; K, 3.9; Cl, 100; HCO3, 23; Blood Urea Nitrogen (BUN), 9; and creatinine, 0.12 liters (normal, 0.3 to 0.7 liters).

§Specific values are as follows: urine Na, 93; urine K, 86.5; and urine Cl, 124.