ID Flashcards
what are RNA viruses?
RNA viruses include influenza, measles, mumps, colds, meningitis, polio, retroviruses (AIDS, T-cell leukaemia), arena viruses, all considered, single descriptor RNA (ssRNA). RNA virus does not enter the cell centre (in addition to the cold virus contamination this season). Viral RNA is then used to make a DNA copy of the viral RNA, which is organised by the host genome followed by a retroviruses.
What are DNA viruses?
Viruses such as poxviruses, herpes, adenoviruses and papilloma viruses usually contain double-stranded DNA, leaving single-digit DNA. DNA virus enters the cell centre and leads to new viruses.
targets for antivirals?
nucleic acid polymerase, protease, integrases, neuraminidases
acyclovir/valgancyclovir
viral DNA polymerase is inactivated in
zanamivir, oseltamivir, peramivir, and laninamivir
neruaminidase (influenza)
Interferon-α and ribavirin
remains the backbone treatment for chronic hepatitis C
mechanism of resistance antivirals?
The major mechanisms for drug resistance are mutations in the viral DNA polymerase gene or in genes that encode for the viral kinases required for the activation of certain drugs such as acyclovir and ganciclovir
Sporotrichosis
rare fungal infection, but most cases of sporotrichosis are reported from North America, South America, and Japan., decaying vegetation and has been isolated most commonly from sphagnum moss, rosebushes, barberry, straw, and some types of hay, Transmission from bites and scratches of animals, most commonly cats and armadillos, has occurred.Disease in humans usually follows cutaneous inoculation of the fungus into a minor wound. Pulmonary infection can result from the inhalation of large numbers of spores.
Cutaneous sporotrichosis is the most common form of disease in all age groups. painless erythematous papule develops at the inoculation site. The initial lesion is usually on an extremity in adults but is often on the face in children
Rickettsia rickettsii
Among them are the tickborne agents Rickettsia rickettsii, the cause of Rocky Mountain or Brazilian spotted fever
tick bites and flea bites
RMSF is the most frequently identified and most severe rickettsial disease in the United States. It is also the most common vector-borne disease in the United States after Lyme disease. Although considered uncommon, RMSF is believed to be greatly underdiagnosed and underreported. RMSF should be considered in the differential diagnosis of fever, headache, and rash in the summer months, especially after tick exposure. Because fulminant disease and death are associated with delays in treatment, patients in whom the illness is clinically suspected should be treated promptly.
fever, headache and rash on soles and palms. petechial
hepatic issues/
coxiella burnetii
inhalation of infected aerosols,
cattle, sheep, goats, rabits
fever headache, myalgias
scrub typhus
he causative agent of scrub typhus, or tsutsugamushi fever, is O. tsutsugamushi, which is distinct from other spotted fever and typhus group rickettsiae
transmision: O. tsutsugamushi is transmitted via the bite of the larval stage (chigger) of a trombiculid mite (Leptotrombidium), which serves as both vector and reservoir. Vertical transovarial transmission (passage of the organism from infected mites to their progeny)
A single painless eschar with an erythematous rim at the site of the chigger bite is seen in 7–68% of cases, and a maculopapular rash is present in less than half; both can be absent.
Nocardia
Pediatric patients with compromised cellular immunity are at particular risk, including children receiving immune suppression after solid-organ or stem cell transplantation, chemotherapy for malignancy, prolonged corticosteroid therapy, children with poorly controlled HIV infection, or those with a primary immunodeficiency, especially chronic granulomatous disease
Ehrlichiosis and Anaplasmosis
All of these organisms are tick-transmitted and are small, obligate intracellular bacteria with gram-negative-type cell walls.
E. chaffeensis and E. ewingii is A. americanum, the Lone Star tick
mimics rocky mountain spotted fever
lymphohistocytosis: all cell lines down. non specific
ddx: Because of the nonspecific presentation, ehrlichiosis mimics other arthropod-borne infections such as RMSF, tularemia, babesiosis, Lyme disease, murine typhus, relapsing fever, and Colorado tick fever. Other potential diagnoses often considered include otitis media, streptococcal pharyngitis, infectious mononucleosis, Kawasaki disease, endocarditis, respiratory or gastrointestinal viral syndromes, hepatitis, leptospirosis, Q fever, collagen–vascular diseases, hemophagocytic syndromes, and leukemia.
