Infectious Diseases Important Notes

Gas gangrene
- Caused by clostridium perfrigens
- It is characterised by skin color change from pallor to bronze/ purple
- Skin is tense and tender
- Gas in the tissues is elaborated by crepitus or visible on radiograph
- Treatment
- Surgical debridement
- Antibiotic therapy with high dose of 4 penicillin, clindamycin, and metronidazole
- Hyperbaric oxygen therapy
Hyperbaric therapy is used for treatment of
- Gas gangrene
- Osteoradionecrosis
- Chronic osteomyelitis
Rubella ( German measles)
- It is caused by a paramyxovirus
- It is spread by droplet infection
- It is characterised by Koplik’s spots on the buccal mucosa which is seen as small white spots surrounded by erythema
- It is followed by the appearance of rash first on the back of ears and at hairline and maximum on face
- Rubella in early pregnancy causes
  - Congenital abnormalities like deafness
  - Spontaneous abortion
  - Congenital heart diseases like persistent patent ductus arteriosus, atrial septal defect, etc
- Complications
  - Pneumonia
  - Encephalitis
  - Otitis media
Hepatitis E
- It is also called Non-A or Non-B hepatitis
- Caused by HEV which is an RNA virus
- Spreads by faeco oral route
- Clinical illness resembles hepatitis A infection
- Pregnant women are particularly liable to acute hepatic failure
- Epidemics are almost exclusively caused by hepatitis E virus
Viruses and infections caused by them
Classification of virus
- DNA Virus
  - Pox viridae
    - Small pox
    - Molluscus
    - Contagiosum
  - Herpesviridae
  - Adenoviridae
    - Major cause for nonbacterial pharyngitis and tonsillitis
  - Papovaviridae
  - Hepadnaviridae
- RNA Virus
  - Picornaviridae
    - Polio
    - Coxsackie
    - Hepatitis A
    - Rhinovirus
  - Orthoviridae
    - influenza
- Paramyxoviridae
- Retrovirus
- Togaviridae
- Rhabdoviridae
- Flaviviridae
- Calciviridae
Types of fever In different infections
- Saddleback fever – dengue
- Step ladder fever – typhoid
- Pell Ebstein fever – brucellosis and Hodgkin’s disease
- Double rise of temperature in a day – kalaazar
Clinical features of syphilis
- Congenital syphilis
  - Hutchison’s triad
  - Saddle nose
  - Sabre tibia
  - Rhagades
  - Bossing of frontal and parietal bones
  - Hypoplastic maxilla
  - Salt and pepper scars on retina
- Primary syphilis
  - Painless chancre
  - Painless palpable rubbery inguinal lymph nodes
- Secondary syphilis
  - Fever, malaise
  - Maculopapular rash on trunks and limbs
  - Condylomalata
  - Mucous patches in the genitalia, mouth, and pharynx
  - Snail track ulcers in mouth
- Tertiary syphilis
  - Gumma
  - Cardiovascular syphilis
  - Aortitis
  - Aortic aneurysm
  - Aortic incompetence
  - Neurosyphilis
  - Tabesdorsalis
  - Meningovascular disease
  - General paralysis
Complications of different infection
Rashes in different diseases
Spots in different diseases