Can Nocardia be acid-fast stain?

Nocardia are weakly acid-fast following staining with the modified Ziehl-Neelsen or Kinyoun stain. Cultures may grow in a few days, but typically require 2 to 3 weeks of incubation.

Is Nocardia and Mycobacterium?

The laboratory diagnosis is based on microscopy and culture isolation, but Nocardia can be mistaken for Mycobacterium, as they not only grow in specific media for mycobacteria, but also form partially acid-fast beaded branching filaments, similar to those formed by rapidly growing mycobacteria18.

How do I know if I have Nocardia?

Members of genus Nocardia are characteristically gram-positive, weakly acid-fast, strictly aerobic, filamentous branching bacilli that fragment into rod or coccoid shaped forms. Nocardia species are ubiquitous environmental bacteria capable of causing opportunistic infections in both human and animals [1, 2].

Is GMS a special stain?

Special stains, such as GMS and PAS, may be useful in highlighting the organisms.

What are the different types of staining techniques?

Types of staining techniques. Simple staining.

What is special staining techniques?

“Special stains” are processes that generally employ a dye or chemical that has an affinity for the particular tissue component that is to be demonstrated. They allow the presence/or absence of certain cell types, structures and/or microorganisms to be viewed microscopically.

What does the GMS stain on block A1 mean?

GMS positive fungus in tissue helps confirm a positive culture result for environmentally ubiquitous fungi (versus contaminant) Comment: GMS stain on block A1 shows broad, nonseptate fungal hyphae with right angle branching, associated with tissue necrosis and angioinvasion, consistent with invasive fungal sinusitis.

How is Nocardia spp.different from Actinomyces?

Nocardia spp. produces pneumonia primarily in the immunosuppressed host. The organism shares morphological and histochemical staining features with Actinomyces, but its clinical and histological responses are usually easily distinguished.

What are the filaments of a Nocardia bacteria?

Nocardia species are thin, aerobic, gram-positive bacilli that form branching filaments. The bacteria stain irregularly and appear beaded on Gram stain. The speciation of Nocardia has been problematic.

What makes a Nocardia a Gram positive organism?

Nocardia are gram-positive (of variable intensity) and have a branching, filamentous appearance. The mycolic acids make them variably acid fast, a fact that can be exploited for identification purposes by using weak acids for decolorization.