RESUMO
There have been some cases where abnormal histopathologic findings could not be found in the kidney could even with proper specimen collection through percutaneous renal biopsy (PRB) in accordance with its indication. We analyzed the incidence and clinical outcomes of children who showed normal histopathological findings in their PRBs. Methods: The medical records of 552 pediatric subjects who underwent PRB between 2005 and 2016 were reviewed. Twenty-six subjects were excluded because allograft biopsy was performed in nine subjects, and the age at biopsy was greater than 18 years in 17 subjects. Finally, 526 subjects were enrolled in this study. Results: Of the 526 pediatric patients, 32 (6.1%) showed no histopathological abnormalities in their PRBs. The male-to-female ratio of the patients was 1.9:1, and the mean ages at the first visit and at biopsy were 10.6 ± 4.1 and 11.4 ± 3.8 years, respectively. In accordance with the biopsy indications, recurrent gross hematuria showed the highest incidence rate, but combined hematuria and proteinuria had the lowest incidence rate regarding normal renal histopathology among all the subjects. At a mean follow-up of 35.5 ± 23.6 months, urinary abnormalities had improved in more than 50% of the subjects with normal renal histopathology, and none of the patients showed progression to end-stage renal disease or required rebiopsy due to symptom worsening during the follow-up period. Conclusion: The clinical outcomes of children with normal PRB histopathologic findings are generally good. Further studies to evaluate their long-term outcomes are needed.
RESUMO
KCNQ2 mutations induce a neonatal-onset epileptic encephalopathy of widely varying severity, ranging from benign familial neonatal epilepsy to severe refractory epileptic encephalopathy. Refractory seizures with KCNQ2 mutations have a positive response to sodium-channel blockers. Recently, a distinctive ictal pattern has been reported during amplitude-integrated electroencephalographic (aEEG) monitoring in infants with KCNQ2 encephalopathy. Herein, we describe a case of KCNQ2 encephalopathy with this distinctive ictal aEEG pattern, which was confirmed using conventional electroencephalography (EEG). A 3-day-old female infant presented with neonatal seizures accompanied by cyanosis and desaturation. Her seizure semiology was tonic and focal clonic. Her ictal aEEG demonstrated a sudden rise in amplitude followed by a suppressed background pattern. This pattern was also confirmed on conventional EEG. Her seizures were refractory despite the administration of multiple conventional antiepileptic drugs. Finally, c.794C>T; p. (Ala265Val) mutation was observed in the KCNQ2 gene on genetic testing, and she was diagnosed with KCNQ2 encephalopathy. Identifying this distinctive ictal pattern on aEEG monitoring facilitates the early detection of KCNQ2 encephalopathy and timely targeted treatment in patients with refractory seizures.
RESUMO
KCNQ2 mutations induce a neonatal-onset epileptic encephalopathy of widely varying severity, ranging from benign familial neonatal epilepsy to severe refractory epileptic encephalopathy. Refractory seizures with KCNQ2 mutations have a positive response to sodium-channel blockers. Recently, a distinctive ictal pattern has been reported during amplitude-integrated electroencephalographic (aEEG) monitoring in infants with KCNQ2 encephalopathy. Herein, we describe a case of KCNQ2 encephalopathy with this distinctive ictal aEEG pattern, which was confirmed using conventional electroencephalography (EEG). A 3-day-old female infant presented with neonatal seizures accompanied by cyanosis and desaturation. Her seizure semiology was tonic and focal clonic. Her ictal aEEG demonstrated a sudden rise in amplitude followed by a suppressed background pattern. This pattern was also confirmed on conventional EEG. Her seizures were refractory despite the administration of multiple conventional antiepileptic drugs. Finally, c.794C>T; p. (Ala265Val) mutation was observed in the KCNQ2 gene on genetic testing, and she was diagnosed with KCNQ2 encephalopathy. Identifying this distinctive ictal pattern on aEEG monitoring facilitates the early detection of KCNQ2 encephalopathy and timely targeted treatment in patients with refractory seizures.