Effective Techniques in the Definitive Diagnosis of Lyme Disease

Lyme disease is the most prevalent vector-borne bacterial infection caused by the spirochete Borrelia burgorferi [1]. In the United States, transmission occurs via its tick vector Ixodes scapularis [2]. According to the CDC, Lyme disease is the most commonly reported vector borne illness, with its density the highest in the Northeastern United States and upper Midwest United States [3]. Because of this, proper diagnosis of this disease is imperative, however, Lyme disease is commonly misdiagnosed as another condition, or over-diagnosed in patients with non-specific symptoms [4]. This article aims to evaluate the various techniques for the diagnosis of Lyme disease to determine which standard is most efficacious for an accurate and definitive diagnosis. SIGNS, SYMPTOMS AND IMAGING Signs, symptoms, and imaging studies are pivotal cues in honing the differential diagnosis, and thus play a key role in differentiating Lyme disease from other maladies with common pathological features. In early Lyme disease, many signs and symptoms are non-specific and could be caused by a wide variety of etiologies, however one of the most specific and common signs of early Lyme disease is the development of erythema migrans (EM) [5]. EM can present in many fashions such as homogenous, central erythema, and central clearing, with homogenous EM being the most common [5]. However, EM-like rashes can sometimes appear with other etiologies, such as from Lone Star Tick bites [6]. Occasionally, these bites can appear indistinguishable from EM and thus possibly result in a misdiagnosis [6]. Therefore, even though EM is one of the most prevalent and specific signs of Lyme disease, non-experienced providers could potentially be misled. Furthermore, many individuals do not remember a tick bite and do not develop EM, further complicating the sole use of EM in the diagnosis of Lyme disease [7]. This illuminates the paramount role of laboratory testing in these patients. Neurologic progression of Lyme disease, a manifestation seen in approximately 12% of patients, produces symptoms which have diagnostic relevance [3]. In a study examining the chronic neurologic manifestations of erythema migrans borreliosis, 50% of the patients experienced cranial nerve impairment, with cranial nerve VII and cranial nerve VIII palsies being the most prevalent cranial nerve manifestations [8]. Approximately 66% of the participants experienced para and tetraspasticpareses [8]. Other abnormalities such as ataxia, bladder dysfunction, and psychiatric disorders were also reported, but were not as prevalent [8]. The symptoms gain specificity as they are consolidated while individually, they can mimic a wide variety of diseases. However, the symptoms reported in this study manifested late in the progression of the disease (7 months to 12 months until diagnosis), making them generally unreliable for early Lyme disease or in patients without neurologic involvement. It appears that children with Lyme disease also appear to have neuroimaging findings that correlate with cranial nerve disorders, according to a study by Ramgopal et al., This study evaluated neuroimages of children who presented with concurrent intracranial hypertension and Lyme disease. Of the seven total patients in the study, six received a contrast enhanced MRI of the brain and orbits, all of which showed cranial nerve involvement in at least two cranial nerves [9]. Symptoms of these patients upon presentation were also vague, with all patients presenting with a headache, four of the seven patients presenting with diplopia, six patients presenting with nausea/vomiting, and four patients presenting with photophobia [9]. This suggests that cranial nerve involvement in Lyme disease is prevalent, though symptoms related from this involvement may not always be apparent [8,9]. Though Lyme disease in conjunction with intracranial hypertension is rare, cranial nerve enhancement has been seen elsewhere in patients presenting with neurologic manifestations of Lyme disease [10,11]. In patients presenting with an array of neurologic symptoms that appear to follow a bacterial infection, particularly in patients that do not have evidence of a tick bite or EM, neuroimaging with signs of cranial nerve enhancement should draw suspicion to Lyme disease as a differential diagnosis. Aside from clinical aspects, geographic location should not