。
She's suffering from gout.
Literal
She [topic-は] gout [object-を] is-ailing.
病む ('to be ill / to suffer from') is a literary and somewhat old-fashioned verb — the modern equivalent would be ~にかかっている or ~を患っている. 痛風 ('gout,' literally 'pain-wind') is a Sino-Japanese medical term. ~でいる marks the ongoing state of illness.