A 25-year-old woman, gravida 1 para 1, comes to the office with her husband for an 8-week postpartum visit. The pregnancy and delivery were normal and without complications. The patient says, "I'm exhausted and sleep deprived but doing okay." Her husband is concerned about her extreme fatigue; he says she has gotten weaker and unsteady over the past week. He also says she has not been holding the baby as often and rarely goes upstairs to the nursery. The patient reports no depressed mood or appetite changes; she elected to bottle-feed. Medical history is unremarkable. Blood pressure is 126/84 mm Hg, and pulse is 80/min. On physical examination, the patient appears tired; gait is unsteady. There is no scleral icterus, and the mucous membranes are pink and moist. The thyroid is not enlarged. Heart and lung sounds are normal, and the abdomen is soft and nontender. There is bilateral lower extremity weakness, left side more than right. Knee reflexes are increased bilaterally. Genital examination shows the vaginal laceration has healed well, and there is no vaginal discharge. Serum TSH is normal. Which of the following is the most appropriate next step in management?
Fatigue and poor sleep are common in the postpartum period. However, this patient's significant fatigue is accompanied by concerning neurologic findings, including:
This episode is very suspicious for a first presentation of multiple sclerosis, an autoimmune inflammatory demyelinating disease of the CNS that typically presents in young adults, especially women of child-bearing age. Extreme fatigue unrelated to activity levels often precedes the development of focal neurologic findings. Although pregnancy is protective for multiple sclerosis (possibly due to the immunosuppressive effects of pregnancy), there is an increased risk of both the initial presentation and subsequent relapses in the early postpartum period.
An MRI of the brain and spinal cord should be obtained. MRI lesions are due to inflammatory plaques and can often be correlated directly to the clinical presentation. Typically, multiple, scattered, ovoid lesions are seen in the periventricular regions and the spinal cord. Imaging findings can often confirm dissemination in space (multiple CNS locations) and time (age of lesions), which are required to confirm a diagnosis of MS.
(Choices A and E) All postpartum patients should be evaluated for depression; cognitive-behavioral therapy and/or selective serotonin reuptake inhibitors are appropriate first-line treatments. However, this patient has no mood changes and has very concerning associated neurologic features (weakness with upper motor neuron signs) that cannot be explained by a mood disorder. Any patient who demonstrates neurologic deficits must undergo additional evaluation to rule out medical causes before a primary psychiatric illness is considered.
(Choice C) Although fatigue and weakness can be seen in postpartum thyroid dysfunction, this patient has a normal TSH, which is a reasonable screening test. In addition, this patient lacks other characteristic symptoms of hypothyroidism (eg, cold intolerance, constipation, dry skin) and has hyperreflexia, which is not expected in patients with hypothyroidism.
(Choice D) Fatigue due to sleep deprivation is common in new parents. However, reassurance is inappropriate when new-onset neurologic symptoms and functional deficits are present.
Educational objective:
Multiple sclerosis can initially present (or often worsens) in the postpartum period. When multiple sclerosis is suspected, MRI of the brain showing demyelinating plaques disseminated in time and space can help confirm the diagnosis.