The lack of H-reflex as an additional neurophysiological sign of development of acute inflammatory demyelinating polyneuropathy in children

Early diagnosis of acute inflammatory demyelinating polyneuropathy (AIDP) is of fundamental importance for the timely prescription of therapy. The conventionally used techniques of electrophysiological diagnosis are not sensitive enough at early stages of development of the condition.

The objective of this work was to assess the applicability of studying H-reflex as a tool for early diagnosis of AIDP in children.

Materials and Methods. A total of 57 children were examined: 20 healthy children (range: 7–14 years; mean age 12 years) and 37 patients diagnosed with AIDP (range: 8-13 years; mean age 11 years). Electroneuromyography (ENMG) was performed on day 3–7 after the first symptoms had emerged. The velocity of impulse conduction along motor fibers, the amplitude of M responses during stimulation of nn. tibialis, ulnaris and medianus, as well as latency and threshold of M response and H-reflex during stimulation of m. soleus, was evaluated.

Results. No significant intergroup differences in amplitudes of motor responses and the velocity of impulse conduction were recorded, while the residual latency of M-response was significantly higher in the AIDP group. In individuals in the control group, the H-reflex was recorded in 100% of cases, while being recorded only in 2 (5.4%) patients in the AIDP group. In both patients, examination was performed as early as possible (day 3) after the onset of the first symptoms among the entire group examined.

Conclusions. In pediatric patients with AIDP, which develops on day 3–7 after the onset of the first symptoms, no H-reflex was recorded in 94.6% of cases. Investigation of the H-reflex at the early stage of AIDP in children can be used as an additional criterion for diagnosing the disease.