U01.03.008 Urease-positive organisms Urease-positive organisms produce the enzyme urease, which hydrolyzes urea into ammonia and carbon dioxide, increasing the pH of their environment. This enzyme aids bacterial survival and virulence, especially in the urinary tract and stomach. Common urease-positive organisms include Proteus, Klebsiella, Helicobacter pylori, Ureaplasma, Nocardia, Cryptococcus, and Staphylococcus saprophyticus.

Learn key urease-positive organisms and their role in infection and diagnosis. #UreasePositive #Microbiology #Proteus #Klebsiella #HelicobacterPylori #StaphylococcusSaprophyticus #Ureaplasma #Nocardia #Cryptococcus #USMLE #MedicalEducation #ClinicalMicrobiology #BacterialMetabolism

U01.03.008 Catalase-positive organisms Read the passage carefully and fill in the missing terms in the blanks. Focus on the key pathophysiology of chronic granulomatous disease (CGD): identify the defective enzyme, the role of neutrophils, and which microbes pose a high infection risk. Use context clues from the sentence structure to drag each correct term into the appropriate box.

Understand catalase-positive organisms and their role in infections, especially in chronic granulomatous disease. #CatalasePositive #Microbiology #CGD #Immunology #Staphylococcus #Pseudomonas #Serratia #Nocardia #Aspergillus #USMLE #MedicalEducation #Pathogenesis #OxidativeBurst

Organisms that stain #modified #AFB positive: #Mycobacterium
#Legionella #micdadei (in specimens only)
#Nocardia
#Rhodococcus
#Tsukamurella
#Gordonia

#idSky #idboardreview

Sporotrichoid Skin Infection Caused by Nocardia brasiliensis in a Kidney Transplant Patient Prompt and accurate diagnosis of Nocardia skin infections is important in immunocompromised hosts, especially transplant patients. The sporotrichoid form, which is otherwise known as the lymphocutaneo...

Yellowish white colonies growing on Sabouraud dextrose agar without chloramphenicol identified by 16SrRNA as #Nocardia brasiliensis. www.mdpi.com/2079-9721/6/...

#nocardia Empiric tx w/ amikacin & Carbapenem & tmp-smx disseminated dz or IC host. Adjust based on susceptibilities

Mri brain should be performed in all pulmonary & disseminated #nocardia cases. Micro lab should be informed of suspecting nocardia as may not grow on regular media. Generally takes3-5d to grow but may take several wks

#Nocardia aerobic, partially acid-fast, branching, filamentous, slow growing Gram-positive bacilli. Infection acquired by direct inoculation or inhalation & spreads hematogenously from lungs. Six forms: pulmonary, systemic, CNS, extrapulmonary, cutaneous & actinomycetoma

#nocardia isolated cutaneous: abx for 3 to 6 months, although patients with mycetomas require 6 to 12 months. Immunocompromised patients with cutaneous disease should generally be treated for a minimum of one year

#nocardia clinical improvement is generally ev ident in 3-5days or most 7-10days after appropriate abx.

#nocardia tmp-smx is mainstay of therapy. Monotherapy usually successful in isolation skin infection or mycetoma that are not extensive.

#nocardia Skin biopsy typically positive on gram stain. Growth of nocardia may take 48 hrs to several weeks but typically 3-5 days. Species identification may be predictive of antimicrobial susceptibility, often requires molecular identification

#Nocardia primary skin infection present as superficial cellulitis or pyogenic abscess, lymphocutaneous (this case), or chronically progressive, destructive disease with sinus tract (mycetoma), usually on distal limb. Inform lab as may not grow by routine methods.

#Nocardia Ref www.ajtmh.org/view/journal...