Download - A Rash Decision - A case study on Lyme Disease

Canterbury Health Laboratories

A RASH DECISION

Rebecca Dew BSc, Grad Dip SciSerology/Virology


Presenting Complaint

• 60 year old man• Originally from Scotland• 5-6 year history of a slowly extending rash• No foreign travel


Presenting Complaint

• Right arm• Thickening over elbow


Early Infection

• Bluish/red discolouration with swelling• Extensor surfaces hands and feet• Unilateral

http://www.dermis.net/bilder/CD020/550px/img0022.jpg


Over the Years

• Extends over months to years• Oedema resolves as atrophy develops• Prominent underlying veins

http://www.dermis.net/bilder/CD035/550px/img0086.jpg


Late Infection

• Fibrous induration/ nodules over bony prominences• Sclerotic lesions can cause peripheral nerve or joint

damage


Histology

• Acrodermatitis chronica atrophicans


To Recap……

• Deer farmer in the Highlands of Scotland• What’s your answer?


Lyme Disease

• Positive Lyme serology• Western Blot

– 3 bands to Borrelia burgdorferi– 7 bands to B. afzelii

• No identified tick bite• Known cases among

co-workers


Castor Bean Tick

• Ixodes ricinus– B. burgdorferi– B. afzelii– B. garinii


Symptoms and Clinical Features

• Tick bite• “Bulls-eye” rash• Multiple and chronic multisystem complications

– Arthritis

• Neuroboreliosis


Reported Cases of Lyme Disease by Year, United States, 2002-2011

Centre for Disease Control and Prevention


Treatment

• Antibiotics - Generally, recovery will be quicker and more complete the sooner treatment begins

• Oral antibiotics - early-stage Lyme disease

– Doxycycline for adults and children older than 8, or amoxicillin or cefuroxime for adults, younger children, and pregnant or breast-feeding women

• Intravenous antibiotics - CNS involvement.


Prevention

• Long sleeves and long pants

• DEET

• Check, check and check again…….

• Vaccination???


And to finish….

• Dr Richard Clinghan

• Dr Sophie Wen