RT Journal A1 ARNON SS, CLAY SA, JOHNSON RO T1 INfant botulism-reply JF American Journal of Diseases of Children JO American Journal of Diseases of Children YR 1979 FD December 1 VO 133 IS 12 SP 1288 OP 1288 DO 10.1001/archpedi.1979.02130120080022 UL http://dx.doi.org/10.1001/archpedi.1979.02130120080022 AB In Reply.—We thank Drs Snyder and Bicknell for their letter that further documents the usefulness of EMG studies in patients with suspected infant botulism. Their observation that the muscle action potential is more enhanced at 50 cps than at 20 cps is noteworthy and should prompt the examiner especially to use the 50 cps frequency. Since EMG study of patients with infant botulism may show either the characteristic brief, small, abundant motor-unit action potentials (BSAP) pattern or enhancement of the evoked response by rapid repetitive stimulation, or both, these patterns should be sought when infant botulism is suspected. In the experience of one of us (S.A.C.), BSAP has proved the more helpful of the two patterns, but we fully concur with Drs Snyder and Bicknell that more bacteriologically proved cases of infant botulism should be studied at 50 cps. Whether one or both patterns is observed, EMG remains the