TPO and hematocrit: The classic form of HT typically presents during the fifth decade of life and is overwhelmingly more common in women (approximately a female-to-male ratio of 4:10).[3] HT, diagnosed by a demonstration of circulating antibodies to thyroid antigens, mainly thyroperoxidase antibodies (TPOAbs) and thyroglobulin antibodies (TgAbs), remains a complex and ever expanding disease of unknown pathogenesis.