Michael Jackson's biographer says the singer is suffering from a rare lung condition that could kill him without an emergency transplant, Fox News reports.

For years, Jackson has suffered from Alpha-1 antitrypsin deficiency, which means his liver doesn't produce enough of a protein that protects the lungs from neutrophil elastase, which, unchecked, attacks healthy lung tissue.

But Ian Halperin says the condition has gotten much worse and that Jackson needs a lung transplant, but he "may be too weak to go through with it." What's more, Jackson also suffers from gastrointestinal bleeding and emphysema, can barely speak and is almost entirely blind in one eye, according to Halperin.