Mode
Text Size
Log in / Sign up

Rare overlap of myasthenia gravis and Kennedy's disease identified in case reportRare Overlap Syndrome Linked to Myasthenia Gravis and Kennedy's Disease

AI-generated summary of the cited source, checked by automated accuracy review. How we work

Key Takeaway
Consider the rare overlap of myasthenia gravis and Kennedy's disease when evaluating patients with atypical neuromuscular symptoms.

This is a case report and literature review describing a single patient with acetylcholine receptor (AChR) antibody-positive myasthenia gravis (MG) and Kennedy's disease (KD), along with a review of previously reported cases. The patient was definitively diagnosed with overlap syndrome based on neurophysiological findings and androgen receptor gene testing. The literature review identified 4 additional cases of KD patients exhibiting myasthenic features, all of whom were AChR antibody-negative.

The authors aim to improve clinicians' recognition of this rare overlap syndrome and explore potential comorbid mechanisms. Limitations include the very small sample size (1 case report, 4 literature cases) and the retrospective nature of the review. No information on treatment, outcomes, or follow-up was reported.

Given the rarity of this overlap, the findings are primarily descriptive and hypothesis-generating. Clinicians should be aware that MG and KD can coexist, but the evidence is too limited to guide specific management changes.

How this fits prior evidence

This case report extends prior coverage of myasthenia gravis overlap syndromes, such as the May 2026 case report of thymoma-associated stiff person syndrome and MG. It also contrasts with the May 2026 meta-analysis of efgartigimod for MG, which focused on treatment efficacy rather than diagnostic overlap. The finding that all 4 literature cases were AChR antibody-negative highlights a gap in understanding seronegative myasthenic features in Kennedy's disease.

Doctors reported on a patient who had both Myasthenia Gravis (MG) and Kennedy's disease. This is known as an overlap syndrome. The patient tested positive for acetylcholine receptor antibodies, which are typically associated with MG. Testing also confirmed the presence of Kennedy's disease.

A review of existing medical records found four other cases where patients with Kennedy's disease showed similar muscle weakness. However, those four patients were antibody-negative. This difference helps doctors understand how these two conditions might interact in different people.

Because this report is based on a single case and a small review of only four other cases, the findings are not enough to make broad claims. The study is intended to help doctors recognize this rare situation more quickly. Patients with muscle weakness should talk to their doctor to determine the best treatment for their specific condition.

What this means for you:
A rare overlap between Myasthenia Gravis and Kennedy's disease was identified in a single patient case report.

Common questions

What is the difference between these two conditions?

Myasthenia Gravis is an autoimmune disorder involving acetylcholine receptors. Kennedy's disease is a genetic muscle disorder. In this specific case, a patient was found to have both conditions at once, which is called an overlap syndrome. This happens in very rare instances and requires specialized testing to identify.

How many people have been identified with this overlap?

The report focuses on one specific case of a patient who was antibody-positive for Myasthenia Gravis while also having Kennedy's disease. A review of other literature found four additional cases of Kennedy's disease patients showing similar features, though those individuals were antibody-negative.

Is this finding common in patients with muscle weakness?

No, this overlap syndrome is considered rare. The study was conducted to help doctors better recognize the condition when it appears. Because the sample size is very small, these findings are not yet used to change standard medical practices for most patients.

Study Details

Study typeSystematic review
EvidenceLevel 1
PublishedJun 2026
View Original Abstract ↓
ObjectiveTo investigate the clinical characteristics and electromyographic findings of a patient with acetylcholine receptor (AChR) antibody-positive myasthenia gravis (MG) overlapping with Kennedy’s disease (KD), aiming to improve clinicians’ recognition of this rare overlap syndrome and explore potential comorbid mechanisms.MethodsThe clinical presentation, laboratory results, and neurophysiological features of one case with AChR antibody-positive MG and KD were analyzed. A literature review of MG overlapping with KD was performed.ConclusionNeurophysiological findings and androgen receptor gene testing results were consistent with a diagnosis of KD. Therefore, the patient was definitively diagnosed with overlap syndrome of AChR antibody-positive MG and KD. A literature review identified only four previously reported cases of KD patients exhibiting myasthenic features; however, all were AChR antibody-negative.
Free Newsletter

Clinical research that matters. Delivered to your inbox.

Join thousands of clinicians and researchers. No spam, unsubscribe anytime.