Typical Carpal Tunnel Syndrome or Something More? A Plastic Surgeon’s Experience With Chronic Inflammatory Demyelinating Polyneuropathy

Abstract

Chronic inflammatory demyelinating polyneuropathy (CIDP) typically presents with widespread peripheral motor and sensory deficits that progress over a 2- to 3-month period. In this article, the authors report a case involving a 32-year-old pregnant woman presenting to hand clinic after a 3-month history of bilateral median nerve compression consistent with carpal tunnel syndrome. Carpal tunnel syndrome is a common complaint resulting from pregnancy-associated edema and is typically treated conservatively. However, upon follow-up, this patient displayed new signs of widespread peripheral neurological deficits, prompting a diagnosis of CIDP. In addition to this highly atypical presentation of CIDP, the patient’s symptoms spontaneously remitted throughout the pregnancy requiring no further treatment. This case highlights the heterogeneous nature of neurological disease presentation and the importance in considering alternative diagnosis in what may appear as clear-cut plastic surgery case.

Introduction

Chronic inflammatory demyelinating polyneuropathy (CIDP) is the most common chronic autoimmune polyneuropathy, representing approximately 21% of newly undiagnosed neuropathies. ¹ Although classification of CIDP can be difficult due to the heterogeneous nature of its presentation and clinical course, it is typically characterized by variable distal and proximal muscle weakness, sensory deficits, and loss of deep tendon reflexes presenting between the ages 40 and 60. ^2-6 This pattern of symptoms is then correlated by slowing of proximal and distal conduction velocities and conduction blocks of peripheral nerves, illustrating demyelination on electromyographic (EMG) studies . ^2,5,7 Chronic inflammatory demyelinating polyneuropathy is an acquired autoimmune disease of the peripheral nerves with both humoral and cellular origin. Specific causes are unknown. ^8,9 It is often compared as the chronic counterpart to Guillain-Barre syndrome and in some cases is indistinguishable until prolonged symptoms or relapses occur. ² Correct identification and diagnosis of this disorder is paramount as it is one of the few peripheral neuropathies amenable to treatment. ⁵

Herein, we outline the clinical course of a young pregnant woman presenting to a plastic surgery hand clinic with a referral for carpal tunnel syndrome (CTS). Upon further investigation, this patient was diagnosed with CIDP. Unlike typical CIDP cases, her symptoms spontaneously remitted throughout the course of the pregnancy without medical intervention. This case highlights the importance of alternative neurological diagnoses in patients presenting with seemingly typical pregnancy-related symptoms in plastic surgery.

Case Report

A 32-year-old right hand dominant G1P0 pregnant woman presented to the author’s services with a 3-month history of bilateral hand pain, numbness, and tingling, which were more severe on the right (dominant) hand. Swelling was minimal. The paresthesia and pain matched the median nerve distribution of the palmar aspects of digits 1 through 3. The symptoms began intermittently with no particular trigger in the second month of pregnancy and progressed to be quite disabling. She found the symptoms to be worse with any type of movement of the wrist, reporting the pain as a 7 to 8 of 10. The pain was more severe at night and occasionally caused her to wake from sleep. The patient found it quite hard to perform activities of daily living. There was no reported pain of the elbow or neck and no history of trauma. Acupuncture and night splints of 2-week duration were tried prior to her referral with no improvement. She had no history of carpal tunnel or neuropathies, and the current pregnancy was otherwise unremarkable.

On initial examination of her hands bilaterally, she had a positive Tinel, Phalen, and Durkan test. She did not have any Tinel test at the elbows or worsening pain with neck range of motion. All fingers and wrists possessed full range of motion and good strength. She had normal sensation to light touch along the median, ulnar, and radial nerve distributions and normal capillary refill of all fingers bilaterally. She also had mild tendonitis in both hands. Given that she was pregnant and that her symptoms would likely resolve early after delivery, we advised her to continue splinting and to follow up in 2 to 3 weeks.

Upon follow-up 3 weeks later, her reported hand symptoms had worsened. Additionally, she described instability and difficulty walking. She stated she had fallen multiple times now and was seen in the emergency department for an episode of Bell’s palsy that had since resolved. The author immediately referred her to the neurologist on call for further assessment.

A thorough neurological history and examination was performed. The patient had no previous symptoms of viral infection or fevers during the pregnancy. Her blood glucose, blood pressure, and course of pregnancy were all normal. Family history was unremarkable for any neurological conditions. Physical examination noted worsening pain, as well as new paresthesias of the feet accompanied with poor mobility and gait disturbances. New weakness of the proximal lower extremities and distal muscles of the upper extremities bilaterally was noted. Reflexes were difficult to elicit. Nerve conduction and EMG studies were requested to delineate a demyelinating neuropathy. These studies revealed widespread differential latency of distal nerve conduction velocities, conduction blocks, and decreased amplitude consistent with the diagnosis of CIDP.

The patient’s symptoms continued to improve as the third trimester progressed and have since resolved with the birth of her child. She now possesses full range of motion, no residual sensory deficits, no evidence of hyporeflexia, and only minor pain peripherally, which she reports as not concerning. Neurology has now discharged her from their service with no plan for further follow-up or treatment. Her child is 4 months old and is now being investigated for a unilateral hearing deficit.

Discussion

Chronic inflammatory demyelinating polyneuropathy has been widely described in the literature as a heterogeneous autoimmune peripheral neuropathy. No clear guidelines for initial presentation or diagnosis have been established. ^2,5,10 Typically, progressive multisensory and motor disturbances occur both distally and proximally in the limbs reaching a physiological nadir after at least 8 weeks. ^2,10 However, CIDP characterization is limited in young pregnant women due to its rarity in this population. ^11,12 To the author’s knowledge, this is the first case of CIDP presenting with prolonged exclusive CTS-like symptoms with delayed progression to more widespread manifestations. As a result of this atypical presentation, the true neurological nature of the disease was not appreciated and both the referring physician and plastic surgeon managed the patient as a CTS case initially. Upon follow-up of conservative management, it was noted that the patient was not a case of typical median nerve compression, but rather a more severe neurological disorder.

This case is unique for a number of reasons: (1) the patient showed a disease progression of CIDP unlike that described in the current literature; (2) this neurological condition mimicked CTS for a number of months, resulting in presentation to and management from a plastic surgeon; (3) and finally, the patient, despite late diagnosis, began spontaneously resolving in the third trimester of pregnancy, leading to the decision not to treat by typical steroid, intravenous immunoglobulin (IVIG) infusion, or plasma exchange methods.

Carpal tunnel syndrome is a common complaint during pregnancy due to a chronic edematous state. ^12,13 As a result, pregnant women with CTS-like symptoms are typically managed conservatively with splints and avoidance of triggers until the pregnancy concludes and edema resolves. It is important for plastic surgeons to be able to recognize atypical signs and symptoms of non-structural neurological problems to minimize time to diagnosis and treatment if not recognized in the primary care setting. This patient was a diagnostic challenge, combining atypical presentation with atypical age and progression. While atypical, it has been shown that the relapse rate of CIDP is significantly higher during pregnancy than when affecting the more typical patients. ¹¹ This highlights the need to ensure the appropriate diagnosis is confirmed and the appropriate physicians are involved in managing patients with CIDP. Although in this case a delay in diagnosis did not change management or treatment for the patient, it has been shown that time to diagnosis is important in the treatment of CIDP.

Conclusion

Neurological conditions can be diagnostically challenging both because of their heterogeneous nature and physician’s unfamiliarity to their presentation. This case emphasizes the importance of recognizing other neuropathies that may present with CTS-like symptoms to plastic surgery as well as the utility of a thorough physical history, irrespective of how common the presenting symptoms are.