Examples of granulation tissue can be seen in pyogenic granulomas and pulp polyps. The adjective granulomatous means "characterized by granulomas". Sarcoid has tight epithelioid granulomas and lymphoid infiltrate. The granulomas can be necrotizing or non-necrotizing. One study has suggested a correlation between pyogenic granulomas and Bartonella seropositivity. Both the granulomas as well as the vasculitis tend to occur in association with necrosis. Nevertheless, necrotizing granulomas are a hallmark of this disease. Loosely dispersed macrophages are not considered to be granulomas. Radiographically, both granulomas and cysts appear radiolucent. The diagnosis is established by finding Pneumocystis yeasts within the granulomas on lung biopsies. An important feature of granulomas is whether or not they contain necrosis. Cholesterol clefts or asteroid bodies are present within or outside granulomas. The macrophages in granulomas are often referred to as "epithelioid". Isoniazid reaches therapeutic concentrations in serum, cerebrospinal fluid, and within caseous granulomas. Ocular granulomas resulting from OLM are frequently misdiagnosed as retinoblastomas.