Dr. Mitchell Kleinberg is a pediatrician in Holbrook, New York and is affiliated with multiple hospitals in the area, including St. Catherine of Siena Hospital and St. Charles Hospital. He received his medical degree from Icahn School of Medicine at Mount Sinai and has been in practice for more than 20 years. Dr. Mitchell Kleinberg accepts Aetna, Humana, Cigna, Blue Cross, United Healthcare - see other insurance plans accepted.