Dissociative amnesia in a patient with post-treatment Lyme disease syndrome

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Investigators describe the case of a 41-year-old patient, diagnosed with post-treatment Lyme disease syndrome (PTLDS), who, in addition to exhibiting typical PTLDS symptoms, also showed a severe retrograde episodic-autobiographical and semantic amnesia.

In 2015, the patient exhibited weakness and loss of energy, psychomotor slowing, night sweats, and difficulties with attention.

A few months prior to the onset of symptoms, the man had a low-grade fever and an Erythema Migrans (EM) rash.

He also experienced identity loss, specific phobias, dissociative symptoms, and depressed mood.

Testing for Lyme disease was positive and he began treatment with antibiotics. However, the patient’s psychomotor slowing persisted, along with his depression and he was prescribed Paxil.

Six months later, the man’s condition worsened.

He developed pain in his lower and upper limbs, which effected his mobility. His headaches became more intense and disabling and he reported having learning difficulties.

“The clinical picture was compatible with PTLDS,” the authors state.

In 2019, the patient was admitted to a rehabilitation center to manage his physical symptoms. At this time, his partner reported that he had developed problems with his memory.

The patient’s neuropsychological testing and psychological assessment found he had “impaired intensive attention but preserved selective attention,” the authors state.

“The patient did not remember any episode of his life prior to the illness and his first memory dated back to about 1 year after the diagnosis of Lyme Disease,” the authors state.

The man also no longer knew who he was and was not able to recognize his relatives.

According to the authors, the patient’s “autobiographical amnesia had emerged 6 months after the antibiotic treatment, when the patient’s clinical condition had worsened.”

While his short-term and anterograde memory (ability to create new long-term memories) were intact, the patient’s retrograde and semantic memory were significantly impaired.

“Severe episodic-autobiographical and retrograde semantic amnesia was consistent with some reports of dissociative amnesia,” the authors point out.

Semantic memory is the memory of general knowledge, such as facts and concepts, like vocabulary or knowledge of famous people.²

Retrograde amnesia can involve impaired memory for events (episodic memory) as well as for facts and concepts (semantic memory) to which patients were exposed prior to the onset of their illness.³

The patient continued to suffer from phobias, specifically a fear of contamination and germs, fear of insects, fear of weapons and uniforms, which impacted his daily life.

“The patient insisted on wearing multiple layers of clothing, when forced to go out,” the authors state.

Three years after the diagnosis of PTLDS, the patient still presented marked psychomotor slowing and pervasive deficits in autobiographical and semantic memory.

“We hypothesize that Lyme Disease and its functional sequelae may have triggered dissociative amnesia,” the authors state. Unfortunately, there is currently no treatment for dissociative amnesia.