A search of the TRIP Database located a number of guidelines and eTextbook articles that discuss diagnosis.  A recent American guideline reports on the diagnosis of Lyme Disease [1].  It has a section “Diagnostic Concerns” which discusses various aspects of diagnosis.  This is summarised in the key recommendations as:

“Since there is currently no definitive test for Lyme disease, laboratory results should not be used to exclude an individual from treatment.

Lyme disease is a clinical diagnosis and tests should be used to support rather than supersede the physician’s judgment.”

However, the guideline discusses many other aspects and we recommend you read these at http://www.guidelines.gov/summary/summary.aspx?view_id=1&doc_id=4836

eMedicine, an American online textbook, has a chapter on Lyme Disease [2].  This also has an extensive discussion of diagnosis which, due to length, cannot be reproduced here.  Therefore, we recommend you read the relevant section at http://www.emedicine.com/med/topic1346.htm

Finally, GP Notebook, has a section on the diagnosis of Lyme Disease [3] which states:

“It is worth assessing the risks by considering the pathogenesis and clinical features of Lyme disease - negative serology does not exclude the diagnosis.

In more than half of people affected by this condition there is no history of tick bite.

The diagnosis is confirmed by serologic testing by indirect immunofluorescence or enzyme-linked immunosorbent assays. IgM peaks at 3-6 weeks; IgG appears more slowly and may take months or years.

The diagnosis is unreliable early. Check Treponema pallidum haemoglutination is negative before accepting a positive result.

The antibody is not affected by treatment. ESR is elevated.

Use of the polymerase chain reaction to detect the presence of Borrelia burgdorferi DNA in specimens from patients may become the most reliable means of determining who has been infected with this organism and when infection has been eliminated.”

References

1) Evidence-based guidelines for the management of Lyme disease. Expert Rev Antiinfect Ther 2004;2(1 Suppl):S1-13. (http://www.guidelines.gov/summary/summary.aspx?view_id=1&doc_id=4836)
2) eMedicine. Lyme Disease. 2005 (http://www.emedicine.com/med/topic1346.htm)
3) GP Notebook. Lyme Disease. (http://www.gpnotebook.co.uk/simplepage.cfm?ID=-1610219503&linkID=21419&cook=yes)