Diseases Flashcards
How is malaria spread?
Through the bite of the female anopheles mosquito
Name the five species of protozoa which cause malaria.
- Plasmodium falciparum
- Plasmodium ovale
- Plasmodium vivax
- Plasmodium malariae
- Plasmodium knowlesi
How is malaria diagnosed?
- Thick blood film to identify disease
- Thin blood film to identify species
- Rapid diagnostic tests to detect antigen
What are the symptoms of malaria?
- Fever (usually fluctuating)
- Chills
- Headache
- Myalgia
- Fatigue
- Diarrhoea
- Vomiting
- Abdominal pain
What are the signs of malaria?
- Anaemia
- Jaundice
- Hepaosplenomegaly
- ‘Black water fever’ - dark urine
Briefly describe the pathophysiology of malaria.
- Sporozoites infect hepatocytes in liver
- Develops into schizont
- Schizont bursts and infects red blood cells
- Schizont forms in red blood cell and bursts
Which plasmodium species can form hypnozoites in the liver which can reactivate malaria?
- Ovale
- Vivax
Which plasmodium species causes complicated malaria?
Plasmodium falciparum
Briefly describe the pathophysiology of complicated malaria.
Red blood cells have proteinaceous knobs which bind to endothelial cells and obstruct small vessels.
What are the complications of complicated malaria?
- Vascular occlusion and hypoglycaemia in brain
- Acute respiratory distress syndrome
- Renal failure
- Thrombocytopenia and DIC
- Shock
What is the treatment for uncomplicated malaria?
Chloroquine
What is the treatment for complicated malaria?
- Artesunate
OR - Quinine and doxycycline
What are some supportive measures that can be given in complicated malaria?
- Antiepileptics
- Oxygen
- Diuretics
- Ventilation
- Fluids
- Dialysis
- Broad spectrum antibiotics
- Blood products
What should be given to prevent a malaria relapse?
What precaution should be taken before treatment?
Primiquine
Screen for G6PD deficiency)
Name the virus which causes HIV.
HIV1
Give five risk factors for having HIV.
- Africa
- Homosexuality less accepted
- Men who have sex with men
- IV drug abusers
- HIV positive mother
Briefly describe the pathophysiology of HIV.
- HIV gp120 binds to CD4 receptors
- Cells migrate to lymphoid tissue and virus replicates
- Virions released from host cell by budding
Describe the seroconversion stage of HIV.
Initial stage of the primary infection.
May be accompanied by transient illness after exposure.
Describe the asymptomatic infection in HIV.
Battle between the virus and the immune system.
Some people have generalised lymphadenopathy.
What is AIDS-related complex?
A stage in the HIV infection where constitutional symptoms develop.
What is AIDS?
HIV + an indicator disease
What is the typical time scale from HIV to AIDS?
8 years
What symptoms may be experienced in HIV seroconversion?
- Fever
- Myalgia
- Pharyngitis
- Rash
What are the signs of generalised lymphadenopathy?
Nodes >1cm in diameter at >2 extra-inguinal sites.