1) Infectious Diseases Flashcards
What is infection?
Infection is a process of tissue invasion by microorganisms, characterized by multiplication of these microorganisms in the body of the host to produce disease.
• Cross infection implies transmission of infection between patients as well as patients and health care professionals.
Community acquired infections ?
that may be present at the time of admission or a visit to a hospital or incubating at that time.
Health-Care-Associated Infections previously known as Nosocomial Infections or Hospital-Acquired Infections ?
that could be induced from a source outside the patient’s body (exogenous) or from within the patient’s own body (autogenous) after a visit or admission to a hospital or health care centre.
What are examples of infectious disease?
Viral infection
Bacterial infection
Fungal infection
Parasitic infection
Diagnosis
• History : foreign travel, immigrants, occupation, domestic pets, sexual activity, drug addiction, tattooing, injections and transfusions.
• Examination : oral ulceration, rashes, lymphadenopathy, hepatosplenomegaly
Investigations
- Baseline : FBC and film, CRP, ESR, liver function tests, urinalysis and chest x-ray
- Microbiological examination of body fluids
- Immunodiagnosis : serology : specific IgG, IgM, IgA antigen detection : e.g. ELISA
- Tissue diagnosis : aspiration / biopsy
- Imaging procedures
See slides 9-10
What are the two types of herpes simplex and how is each spread?
• Herpes simplex type 1 spread by infected saliva
• Herpes simplex type 2 spread by sexual contact
What is the incubation period and clinical features of herpes simplex?
• Incubation period is 2-12 days
• Clinical features :
• Orolabialis infection
• sore throat, fever
• vesicles on pharynx, buccal mucosa, gingiva & tongue which spreads to lips and face
• lymphadenopathy
• recurrence
What are the different types of infections of herpes simplex and which virus/viral infection causes them?
- Skin infections
• hsv-1 or hsv-2
• herpetic whitlow
• primary infections - Eye infections
• usually hsv-1
• corneal involvement is serious since it may cause blindness - Genital / anal infections
• usually hsv-2
What are the complications and treatment of herpes simplex?
Complications :
• encephalitis - affects temporal lobes
• neonatal - serious since mortality is 60 %
• due to transfer of HSV-2 during parturition
• indication for a caesarian section
• erythema multiforme
• eczema herpeticum
Treatment :
• Acyclovir, Valacylcovir
Important to recognise due to risk of cross-contamination to other patients
See slide 14
What is herpes zoster and what are the clinical features?
- Reactivation of varicella zoster virus
- Clinical features :
• preceded by radicular pain and hyperaesthesia of overlying skin
• rash - unilateral, dermatomal
• intense erythema which rapidly become vesicles which crust
• oral, palatal or pharyngeal involvement if Trigeminal nerve affected
• ocular involvement causes keratitis or uveitis which may result in blindness
• Ramsay-Hunt Syndrome – reactivation of VZV in the geniculate ganglion of the VII cranial nerve
(HERPES ZOSTER IS SHINGLES)
Complications and treatment of herpes zoster?
Complications :
• post-herpetic neuralgia
• neurological e.g. Meningitis
Treatment :
• acyclovir
• reduces pain / accelerates healing
no effect on post-herpetic neuralgia
What is Infectious mononucleosis caused by, incubation period and clinical features?
- Epstein-Barr virus
- Incubation period is 4-14 days
- Clinical features :
anorexia, malaise, fever
sore throat
cervical lymphadenopathy
macular rash n.b. Ampicillin
tonsillitis with white exudate
palatal petechiae
palpable spleen
jaundice (10%)
Don’t need to know but it is basically MONO what the college students get