Lyme disease can be difficult to diagnose because many of its symptoms mimic those of other disorders. Although a tick bite is an important clue in diagnosis, many patients cannot recall a recent tick bite, since the nymphal stage of the tick is so tiny and a tick bite is usually painless (Figure 8).

Figure 8

When a patient does not develop the distinctive erythema migrans rash, the health care provider must rely on a detailed medical history and a careful physical examination for essential clues to diagnosis, with laboratory tests playing a supportive role.

Assessment

Assessment — a cornerstone of nursing practice — is one of the most critical skills nurses can apply to the early diagnosis and treatment of Lyme disease. Some key questions to consider:

• Does the patient live, play or work in an area endemic for tick infestation?
• Has the patient traveled to other areas where Lyme disease ticks are endemic (refer to map)?
• Does the patient remember being bitten by a tick?
• If so, was the tick removed properly using tweezers?
• What are the patients outdoor activities — gardening, clearing brush or leaves from wooded areas of property, hiking, camping, etc.?
• Have other household members or neighbors been diagnosed with a tick-borne illness?
• Does the patient have pets? If so, is there a history of tick borne diseases or tick attachments with these pets?
• Could the patient's presenting symptoms be attributable to Lyme disease?

With this historical and travel background and a complete physical exam, a practitioner can use disease onset and current status of signs and symptoms to arrive at a diagnosis. If Lyme disease is considered likely, the practitioner will determine which laboratory tests may be necessary.

Figure 9

Assessment Questions Where do you live/work? Were you bitten by a tick? What are your outdoor activities? Do you have a pet (dog or cat)? Has anyone in your home had a tick-borne illness?