Voice Issues May Be Sign of Late-onset MG, Case Report Shows
A 60-year-old man with dysphonia — voice issues when trying to speak — was found to have late-onset myasthenia gravis (MG), according to a recent report.
Voice changes often come with aging, and this may lead to a delayed or even missed diagnosis of the neuromuscular condition, the researchers noted.
His case “highlights the need for physicians to stay alert and have a high suspicion of such probability for timely diagnosis,” the team wrote.
The case report, “A diagnostic dilemma of dysphonia: a case report on laryngeal myasthenia gravis,” was published in the journal Cureus by researchers in Pakistan.
MG symptoms can develop at any age, including during childhood. In about one-third of cases, however, the first symptoms begin after the age of 50. Indeed, in many men, the onset of the disease occurs after age 60. In such cases, patients are said to have late-onset MG.
“Late-onset myasthenia gravis, a rare variant of the disease found in the elderly, has become a diagnostic challenge on account of its atypical presentation,” the researchers wrote.
The disease typically starts with muscle weakness. When muscles of the face, neck, and throat also are affected, it may cause voice issues, with the voice sounding raspy, weak, or nasal.
“Voice changes can be the initial or, in rare instances, the only predominant complaint,” the researchers wrote.
Here, the team described the case of a man treated in Peshawar, Pakistan, who was treated for dysphonia as a first and predominant symptom of late-onset MG.
The man had a history of high blood pressure (hypertension) and heart problems caused by blood vessels narrowing (ischemic heart disease). He visited the hospital with complaints of dysphonia and weakening of cough for the previous month.
His voice sounded hoarse and he had slurred speech. He also experienced mild irregular difficulty in swallowing. Sometimes, food would come up into his nose or get stuck in his throat, according to the healthcare team. Other clinical examinations were unremarkable.
Given their suspicion of potential MG, doctors ordered a test to detect the presence of anti-acetylcholine receptor (AChR) antibodies, a known cause of the disorder. The test came back positive and a diagnosis of MG affecting the voice box, or larynx, was made.
“Laryngeal myasthenia gravis is a very rare variant of late-onset myasthenia gravis,” the researchers wrote, “with only a few cases described so far.”
The patient was started on oral pyridostigmine (two tablets of 60 mg each, four times daily) and oral prednisolone (20 mg per day), which was then tapered off.
Within a month after starting treatment, the patient’s overall health status had improved significantly, according to the team. His speech had improved and his swallowing difficulties had eased.
This patient “was a difficult case to diagnose, especially given his old age,” the researchers wrote, noting that this case is a reminder that MG should be suspected in patients presenting voice changes.