MMIC: Case Study 1

Description of Potential Diseases:

Cat-scratch Disease (A,B)
Transmission vehicle: Most commonly by kittens, also spread by cats & dogs, with fleas as intermediate hosts
Bacteria: Bartonella henselae
Causes: Bites and scratches by infected vehicle, contact with infected vehicle’s saliva on open lesions
Signs and symptoms: Bump or blister at site of injury, swelling of lymph nodes near sit of injury, fatigue, low fever, headache, malaise & enlarged spleen (less common)
Epidemiology: Found world wide (1, 9)

Lyme Disease (A,B)
Transmission vehicle: Ticks on cats and dogs.
Bacteria: Borrelia burgdorferi
Causes: Bite of infected tick.
Signs and symptoms: Fever, skin rash, joint inflammation, and flu-like symptoms
Epidemiology: USA (6, 10)

Rat-bite Fever (A,B)
Transmission vehicle: Fluids in the mouth or nose or urine of an infected rodent.
Bacteria: Streptobacillus moniliformis & Spirillum minus
Causes: Bite of an infected rodent or contact with its secretions
Signs and symptoms: Fever, rash (red or purple plaques), headache and muscle ache.
Epidemiology: Japan, Australia, Africa, North and South America, and Europe. (5, 12)

Rocky Mountain Spotted Fever (A,B)
Transmission vehicle: Ticks on cats and dogs.
Bacteria: Rickettsia rickettsii
Causes: Bite of infected tick
Signs and symptoms: Fever, rash, muscle pain, nausea, vomiting and diarrhea.
Epidemiology: Asia and USA (3, 9)

Toxoplasmosis (A, B)
Transmission vehicle: Most commonly in cats, and also by birds and other animals
Bacteria: Toxoplasma gondii
Causes: Ingestion of contaminated soil, careless handling of cat litter, ingestion of raw or undercooked meat
Signs and symptoms: swollen lymph glands, muscle aches, reduced/blurred vision, fever & headache
Epidemiology: More common in North America (2, 13)

Typhoid Disease (A,B)
Transmission vehicle: Ticks carrying the bacteria previously in contact with chronic stool carrier.
Bacteria: Salmonella typhi & Salmonella paratyphi
Causes: Ingestion of contaminated food or water, sewage & shellfish
Signs and symptoms: Severe headache, fever, loss of appetite, fatigue, constipation, diarrhea, abdominal tenderness, rose spots on lower chest and abdomen, high fever & bloody stools
Epidemiology: Found worldwide, especially in Asia, Africa, Latin America, the Caribbean, and Oceania (4, 7)

Typhus (A,B)
Transmission vehicle: Ticks and fleas on rats and cats.
Bacteria: Rickettsia typhi (murine or endemic) & Rickettsia prowazekii (epidemic)
Causes: Bite of infected flea or tick.
Signs and symptoms: Extremely high fever, dull red rash that begins on middle of the body and spreads, nausea, vomiting and headache
Epidemiology: USA (11, 14)

-------------------------------------------------------
Preliminary diagnosis:

The symptoms of these disease includes rashes, high fever, and general weakness (fatigue) (3, 4, 5, 6, 7, 8, 10, 11, 12, 14):
1. Lyme Disease
2. Rat-bite Fever
3. Rocky Mountain Spotted Fever
4. Typhoid Fever
5. Typhus

Cat Scratch Disease is rejected due to the following reasons:
- The symptoms of Cat Scratch Disease does not include rash, which is one of the prominent features of this situation
- The fever caused by Cat Scratch Disease is low, however, in this situation, the patient's fever is high. (1, 9)

Toxoplasmosis is rejected due to the following reason:
- The symptoms of Toxoplasmosis does not include both general weakness (fatigue) and rash, which are symptoms found on the patient. (2, 13)

-------------------------------------------------------

References:

1. American Uveitis Society. (2003). Cat-Scratch Disease. Retrieved May 5, 2007, from http://www.uveitissociety.org/pages/index.html > Search> Search: Cat scratch disease > Cat-Scratch Disease

2. Centers for Disease Control and Prevention. (2004). Toxoplasmosis. Retrieved April 25, 2007, from http://www.cdc.gov/index.htm > Search: Toxoplasmosis > Toxoplasmosis: Index | CDC Parasitic Diseases > Fact Sheet: Toxoplasmosis

3. Chinese University of Hong Kong. (2006). Rickettsia. Retrieved May 6, 2007, from www.aic.cuhk.edu.hk > Search Rickettsia > Rickettsia

4. eMedicine. (2006). Typhoid Fever. Retrieved May 9, 2007, from http://www.emedicine.com/ > eMedicine Specialties > Medicine, Ob/Gyn, Psychiatry, and Surgery > Infectious Diseases > Typhoid Fever.

5. HeathAtoZ.(2002). Rat-bite Fever. Retrieved 10 May, from, www.healthatoz.com > Search: Rat-bite Fever > Rat-bite Fever

6. Mayoclinic.com. (2006). Lyme Disease. Retrieved May 9, 2007, from www.mayoclinic.com > Search: Lyme Disease > Lyme Disease

7. Medline Plus. (2005). Typhoid Fever. Retrieved May 9, 2007, from www.medlineplus.gov > Medical Encyclopedia > To-Tz > Typhoid Fever

8. Medline Plus. (2005). Rocky Mountain Spotted Fever. Retrieved May 9, 2007, from www.medlineplus.gov > Search: Rocky Mountain Spotted Fever > Rocky Mountain Spotted Fever

9. Medline Plus. (2005). Cat scratch disease. Retrieved April 25, 2007, from http://medlineplus.gov/ > Medical Encyclopedia > C-Cg > Cat scratch disease

10. Medline Plus. (2005). Lyme Disease. Retrieved May 8, 2007, from www.medlineplus.gov > Search: Lyme Disease > Lyme Disease

11. Medline Plus. (2005). Typhus. Retrieved May 7, 2007, from www.medlineplus.gov > Search: Typhus > Typhus

12. Medline Plus. (2005). Rat-bite Fever. Retrieved May 6, 2007, from www.medlineplus.gov > Search: Rat-bite Fever > Rat-bite Fever

13. Medline Plus. (2006). Toxoplasmosis. Retrieved May 5, 2007, from www.medlineplus.gov > Medical Encyclopedia > To-Tz > Toxoplasmosis

14. Wikipedia. (2007). Typhus. Retrieved May 10, 2007, from www.wikipedia.org > Search: Typhus > Typhus

*NOTE*
Direct links under (A,B)

-------------------------------------------------------

Charmaine~
Lizzie~
Adrian~
Joan~
Ye Tun~
Ai Tee~
Kent~