Mucocutaneous lesions Flashcards
Viruses that cause maculopapular rashes
Measles/rubeola
Rubella
Roseola/HHV-6
Fifth disease/parvovirus B19
Viruses that cause vesicular rashes
Chickenpox/VZV
Hand-foot-mouth/Coxsackie
HSV-1
Virus that attaches to CD46, PVRL4, and CD150 receptors of many cells
Measles
Maculopapular rash that starts on face and spreads to extremities
Measles
Presentation of measles
CCCP –> cough, coryza, conjunctivitis, and photophobia
High fever
Exanthema
Exanthema
Rash accompanying a fever
Complications of measles
-Giant cell pneumonia
-Post-infectious encephalitis
-Subacute sclerosing panencephalitis (SSPE)
Koplik’s spot
Grans of salt surrounded by read halo on buccal mucosa in measles
Lab diagnostics for measles
ELISA (IgM)
Immunofluorescence
RT-PCR
ssRNA virus
Paramyxoviridae
Genus Morbillivirus
Measles
ssRNA virus
Togaviridae
Genus rubivirius
Rubella
Prodromal phase symptoms of rubella
Fever
Malaise
Mild sore throat
Coryza
Complications of Rubella
Arthralgia and arthritis
Congenital rubella syndrome
Lab diagnostics for Rubella
ELISA (IgM)
Immunofluorescence
RT-PCR
Complication of Parvovirus B19 and cause
Aplastic crisis due to infection of erythroblast precursors in bone marrow
Complication of Parvovirus B19 in pregnant females
Hydrops fetalis
Lab diagnostics for Parvovirus B19
ELISA (IgM)
PCR
dsDNA virus that multiplies in salivary gland and oropharynx
Roseola
Rash that appears on trunk and neck first, then spreads to face, then to extremities
Roseola
Infected cells show Cowdry type A intranuclear inclusions and form syncytia
VZV
Rash begins in hairline, scalp, and behind ears, then spreads to face, torso, and limbs
VZV
Serious complications in adult cases of VZV
Pneumonia
Encephalitis
Vigorous immune response
Latent in dorsal root and cranial nerve ganglia
VZV
Complications of herpes zoster
Postherpetic neuralgia
Ophthalmic zoster
Ramsey Hunt syndromes
Pathogenesis of Ramsey Hunt syndromes
VZV travels down geniculate ganglion
Symptoms of Ramsey Hunt syndromes
Otalgia
Hemiparesis
Vesicular eruption around the ear
Characteristics of smallpox lesions
Synchronous
Concentrated on face and distal extremities
HSV-1 enters latency here
Trigeminal ganglion
Transmission of Coxsackie virus
Feco-oral
Oral and pharyngeal ulcers, and vesicular rash on palms and soles with mild fever
Coxsackie/Hand-foot-mouth
Laboratory diagnostic tests for vesicular rashes
Tzank smear
Immunofluorescence
ELISA
Immunohistochemistry
PCR (gold standard)
Shown on Tzank smear for vesicular rashes
Multinucleated giant cells/syncytium
Viral inclusion bodies
Used in acyclovir resistant vesicular viral rashes
Foscarnet
Cidofovir
Can be used to prevent recurrence of viral vesicular rashes
Valacyclovir
Famciclovir
Complication of roseola
Febrile seizures
Causes of petechiae, purpura, and/or ecchymosis mucocutaneous lesions
Menigococcemia
RMSF/Rickettsia rickettsii
Dengue fever/flavivirus
Leptospiroses
Lyme disease/erythema chronicum migrans
Hantavirus/Bunyavirus
Rash begins on wrists/hands and ankles/feet and spreads to trunk. It starts as maculopapular and becomes petechial/purpuric
Rocky mountain spotted fever
Complications of RMSF
Splenomegaly
DIC
Shock
Death
Enveloped, isosahedral with positive sense ssRNA spread by Aedes mosquito
Dengue fever
Maculopapular and hemorrhagic rash, retro-orbital pain, muscle and joint pain with fever
Dengue fever
Caused by Borrelia burgdorferi
Lyme disease
Bulls-eye rash with fever, HA, and lymphadenopathy
Lyme disease
Complications of Lyme disease
Meningitis
Encephalitis
Bell’s palsy
Arthralgia and arthritis
Lab diagnostics for Lyme disease
ELISA
Immunofluorescence
Western blot
PCR
Enveloped, negative sense, segemented, ssRNA in rodent excreta
Hantavirus/Bunyavirus
Complications of hantavirus
HPS
HFRS
Non-enveloped, circular dsDNA that replicates in basal keratinocytes
HPV
Koilocytes
Enlarged keratinocytes with clear halos around shrunken nuclei that are characteristic of HPV infections
Nodular to wart-like lesions that later become pearly-white umbilicated nodules with central caseous pus
Molluscum contagiosum virus
Histology of molluscum bodies
Pink, homogenous, intracytoplasmic inclusions seen in biopsy specimens, or in the expressed caseous core of a nodule
Mycolic acid in cell wall and acid fast bacilli
Mycobacterium leprae
Transmission of leprosy
Inhalation and skin contact
Requires prolonged contact