case report
Anxiety and cognitive decline were the chief complaints. Lyme neuroborreliosis was missed.
2026-06-23
Anxiety and cognitive decline were the chief complaints. Lyme neuroborreliosis was missed.
Worsening anxiety and a bite
A 38-year-old woman in Rio de Janeiro, Brazil, lived with a history of generalized anxiety disorder and hypothyroidism. She managed her symptoms with desvenlafaxine and levothyroxine, using alprazolam for rescue. In September 2023, after visiting a forested region near her urban home, she noticed a tick bite on her back. The bite developed into a five-centimeter hyperpigmented lesion that grew slowly and felt occasionally uncomfortable and itchy.
Mental and physical decline
By early 2024, the situation shifted from a local skin irritation to a systemic crisis. The woman reported a significant worsening of her anxiety. More concerningly, she began experiencing cognitive disturbances that impaired her reasoning, concentration, and memory. She suffered from profound fatigue that interfered with her daily activities. At the same time, multiple tense, fluid-filled blisters began appearing on both hands, ankles, and other areas subject to minor trauma.
The signals of inflammation
Laboratory tests revealed that her body was in a state of high inflammation. Her erythrocyte sedimentation rate (ESR) was 90 mm/1 h, more than four times the normal limit, and her C-reactive protein was elevated. Despite these markers, her initial psychiatric-led management focused on her mood and cognitive complaints as distinct from her physical symptoms. An incisional biopsy of the original dorsal lesion suggested an arthropod bite, but it was not until serological testing was performed that the underlying trigger was identified. Diagnosis through ELISA and Western blot confirmed a positive IgM result for Borrelia burgdorferi.
The autoimmune turn
The infection had triggered a secondary autoimmune process. A biopsy of the new blisters revealed subepidermal cleavage and linear IgG deposits, findings consistent with acquired epidermolysis bullosa (EBA). In the advanced stages of Lyme disease, clinical manifestations can transition from an infection to a process where the immune system attacks its own tissues—in this case, producing autoantibodies against collagen VII. This crossover explained why her cognitive disturbances and skin fragility persisted even after an initial short course of antibiotics failed to resolve the condition.
Recovery through combined treatment
To address both the persistent infection and the resulting autoimmune response, a 90-day regimen of doxycycline and dapsone was initiated. The combination therapy resulted in the complete regression of the skin lesions and the normalization of her inflammatory markers. Crucially, the same treatment led to the improvement of her cognitive complaints, anxiety, and fatigue. Following the antibiotics, she began long-term immunomodulation with colchicine and hydroxychloroquine to maintain control over the immune-mediated response.
The medical picture
Erythrocyte sedimentation rate (ESR)
90 mm/1 h
C-reactive protein (CRP)
10 mg/L
Hemoglobin (Hb)
10.9 g/dL
Serology for Lyme (ELISA/Western blot)
Positive IgM
Direct immunofluorescence
Linear IgG deposits along the basement membrane
Adapted faithfully from the open-access case report: Cureus (PMC12542265). DOI: 10.7759/cureus.92859. Read the original at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12542265/.