Asymptomatic infections are also called subclinical infections. Hyperthyroidism and subclinical hyperthyroidism are associated with AF development. Even mild or subclinical hypothyroidism leads to possible infertility and an increased risk of miscarriage. For a complete list of asymptomatic infections see subclinical infection. Asymptomatic conditions also exist (e.g. subclinical infections and silent diseases like sometimes, high blood pressure). Of people with subclinical hypothyroidism, a proportion will develop overt hypothyroidism each year. The chronic form may follow from acute or subacute cases or subclinical infections. If anti-TPO is not positive, treatment for subclinical hypothyroidism is not currently recommended. The chronic carrier state may follow acute illness, or mild or even subclinical infections. He has cerebellar atrophy and subclinical seizures. One study testing genital skin for subclinical HPV using PCR found a prevalence of 10%. The at-risk people might have subclinical coronary disease. Compound heterozygotes are often observed only through subclinical symptoms such as excess iron. Infected piglets born to infected but subclinical sows help maintain the disease within a population. It provides a useful technique for detecting subclinical cases of mastitis.