Brachial and lumbar plexopathies are rare causes of painful paralysis in the upper and lower limbs, respectively. Lumbar plexopathy may be triggered by diabetic amyotrophy or nondiabetic lumbosacral plexopathy. Both of these conditions have been observed to be responsive to corticosteroids, with the potential for spontaneous resolution. A wide range of pathologies may involve the brachial and lumbosacral plexus. These conditions may be categorized as follows: direct trauma; immune, inflammatory or metabolic disorders; cancer and its treatment effects; and other structural conditions.^{Reference Rubin1} Neurological manifestations can precede the other clinical manifestations of Sjögren’s syndrome.^{Reference Colaci, Cassone, Manfredi, Sebastiani, Giuggioli and Ferri2} Peripheral neuropathies and cranial neuropathies are frequently reported as classical neurological manifestations of Sjögren’s syndrome.^{Reference Colaci, Cassone, Manfredi, Sebastiani, Giuggioli and Ferri2} Sjögren’s disease is a rare cause of plexopathy, and we present three such cases in which immunomodulatory medications have been used to treat.

A 30-year-old female presented with a 10-month history of acute onset of a burning sensation in the anterior aspect of the right thigh, which gradually worsened. She also had a history of nocturnal awakenings due to the pain. Four months after the initial onset of this symptom, she began to experience a sensation of numbness in a circular pattern in the anterior portion of the right knee, which subsequently extended to the right thigh. Additionally, she developed a sensation of pins and needles in the right thigh. Around this same time, she has also noticed thinning of the muscles of the front and medial parts of the right thigh along with difficulty in getting up from sitting and in climbing with her right leg. There were no symptoms in the other limbs or sphincter involvement. Examination revealed wasting and weakness of the anterior and medial compartment of the right thigh. Motor power assessment by the Medical Research Council (MRC) was right hip flexion grade 4/5, adduction grade 3/5, abduction and extension was grade 5/5. She had an absent right knee jerk with a preserved ankle jerk. In the L1, L2, L3 and L4 dermatomes, touch, pain and temperature were reduced. A clinical diagnosis of right lumbar plexopathy was made. Her electrophysiological study (EPS) showed spontaneous activity (SA) in the form of positive sharp waves and fibrillations and long-duration and large motor unit action potentials (MUAP) with delayed recruitment and incomplete interference in the right iliacus, vastus lateralis and adductor longus, consistent with right lumbar plexopathy. Etiological possibilities considered were diabetes mellitus, inflammation or infiltration. Her HbA1c and abdominal imaging were normal. Magnetic resonance (MR) neurography showed thickening of the right femoral nerve without enhancement (Figure 1A and B). The CSF examination was normal. The immunological workup revealed a titer of 3+ for both anti-Ro and anti-La antibodies. Schirmer’s test was abnormal with only 3 mm of tear film in the right eye and 2 mm in the left eye after 5 minutes. However, minor salivary gland biopsy was done with no increase in B-lymphocytes (2/10 high power field). The patient was initiated on treatment with methylprednisolone (MPS) 1 g intravenous once daily for 5 days, followed by oral prednisolone 1 mg/kg, oral methotrexate (MTX) 12.5 mg once weekly doses and folic acid. In the next outpatient clinic visit, after 1 month of starting immunotherapy, her power and sensory symptoms improved. Her hip flexion and hip adduction became grade 4+/5, and she had a decrease in pins and needle sensations in the right thigh.

Figure 1.

(A) and (B) Coronal and axial T2 fat-suppressed images reveal thickening of the right femoral nerve (white arrow) without any significant enhancement on (C) post-gadolinium images.

A 58-year-old male presented with complaints of insidiously noticed slipping of slippers with awareness of his left foot and developed left foot drop over 2 months 5 years ago. Three months into the illness, he also had difficulty getting up from a sitting position with flabbiness in his left lower limb. He also felt a decreased perception of hot and cold water on the plantar and dorsal aspects of his left foot. Over a few months,he noticed thinning of the left leg. He gave a history of being treated with injection MPS pulse therapy 5 years ago. He had taken azathioprine and tapering doses of steroids for 5 months. The patient’s sensory symptoms improved temporarily for about 3 months. The patient continued to experience motor symptoms, including foot drop and difficulty climbing, requiring the use of a stick for ambulation over the 5-year period. On examination, his bulk was reduced in the left lower limb with hypotonia. He had MRC grade 4/5 power in his left hip and left knee extension and grade 3/5 power in left ankle dorsiflexion, plantar flexion and left knee flexion. The Deep Tendon Reflexes were notable for absent left knee and bilateral ankle reflexes. There was decreased pain and temperature sensation on the left S1 dermatome by 10%. EPS showed SA in the form of fibrillations and positive sharp waves with long-duration and large unit MUAPs with delayed recruitment and incomplete interference in left iliacus, gluteus medius, gluteus maximus, adductor longus, vastus lateralis, long head of biceps femoris, tibialis anterior, gastrocnemius and peroneus longus consistent with left lumbosacral plexus involvement. Anti-Ro and anti-La antibodies were 3+ positive, and he had a positive Schirmer test. His HBA1c, MR neurography (Figure 2) and CSF examination were normal. Minor salivary gland biopsy was also not contributory. The patient was started on methylprednisolone 1 g intravenous infusion for 5 days, followed by oral prednisolone taper, oral MTX 12.5 mg once weekly and folic acid. In the next outpatient clinic visit after 2 months, his power had improved to grade 5/5 in left hip and left knee extension, but power remained at grade 3/5 in the left ankle dorsiflexion and plantar flexion. His sensory symptoms also improved.

Figure 2.

(A) and (B) Coronal T2 and fat-suppressed images reveal no significant thickening and hyperintensity in any of the lumbar nerve roots/nerves. (C) No significant post-gadolinium enhancement seen on coronal post-contrast images.

A 25-year-old female presented with complaints of paresthesia in the medial aspect of the left followed by the right hand of 3 months duration. Symptoms progressed over the next 10 days such that the patient started experiencing involuntary flexion of the medial two fingers of both hands. This was associated with difficulty in gripping a pen and difficulty in lifting a heavy weight. On examination, patient had wasting of the hypothenar eminence and medial aspect of both forearms. The patient had weakness in all ulnar innervated muscles: abductor pollicis brevis, flexor digitorum profundus, flexor pollicis longus and extensor indicis proprius with absent reflexes bilaterally. Her EPS showed bilateral lower trunk brachial plexus lesion with no SA in cervical paraspinal muscles and normal Sensory Nerve Action Potentials. She had anti-Ro and anti-La antibodies positive with a positive Schirmer test. Her contrast-enhanced MRI plexus protocol showed bilateral lower cervical nerve roots enhancement (Figure 3). A provisional diagnosis of bilateral lower brachial radiculoplexopathy due to Sjögren’s syndrome was made. She was started on immunotherapy with oral prednisolone 1 mg/kg, oral MTX 12.5 mg once weekly and folic acid. The patient was lost to follow-up after commencing immunotherapy.

Figure 3.

(A) Sagittal T2-weighted images reveal normal cervical cord. (B) Coronal T2 fat-suppressed and (C) 3D nerve view images reveal hyperintense signal and mild thickening of the lower cervical nerve roots (right > left). (D), (E) and (F) On post-gadolinium coronal and axial images, there is enhancement of the corresponding nerve roots (white arrows).

Sjögren’s syndrome is characterized by chronic inflammation of exocrine glands such as lacrimal and salivary glands, leading to xerophthalmia and xerostomia. One-third of the patients may present with systemic extra-glandular neurological, articular, pulmonary and gastrointestinal manifestations. Neurological manifestations in primary Sjögren’s syndrome range from 10% to 25 % of cases, most frequently as peripheral neuropathy.^{Reference Bhagavan, Ramaswamy, Khakh and Govindarajan3} Apart from central nervous system involvement, peripheral neurological manifestations are polyradiculopathies, mononeuritis multiplex, painful small fiber neuropathy, autonomic neuropathies and multiple cranial neuropathies. The proposed pathogenic mechanisms responsible for neurological involvement in Sjögren’s syndrome are direct infiltration of the tissue by lymphocytic cells, vascular injury due to anti-neuronal and anti-SSA antibodies and/or ischemia secondary to small vessel vasculitis.^{Reference Colaci, Cassone, Manfredi, Sebastiani, Giuggioli and Ferri2}

The AECG (American-European Consensus Group criteria for Sjögren’s) and ACR (American College of Rheumatology) criteria do not incorporate neurological manifestations of Sjögren’s syndrome for diagnosis. This may lead to delayed diagnosis of patients with initial neurological symptoms.^{Reference Le Goff, Cornec and Jousse-Joulin4} Sensory ganglionopathy, small fiber neuropathy, trigeminal neuropathy, multiple cranial neuropathies, mononeuropathies, polyradiculoneuropathies and autonomic neuropathies are the common peripheral nervous system manifestations of Sjögren’s syndrome.^{Reference Tominaga, Iizuka and Kaneko5} Patients who had systemic manifestations of Sjögren’s syndrome may not be having sicca symptoms. But the diagnosis can be established with labial salivary gland biopsy and anti-Ro/SSA antibody.^{Reference Tominaga, Iizuka and Kaneko5} Plexopathies are rarely reported along with Sjögren’s syndrome. Bhagavan et al. reported a case of brachial plexopathy associated with Sjögren’s syndrome.^{Reference Bhagavan, Ramaswamy, Khakh and Govindarajan3} In this case, after neurological manifestations, the later development of exocrine-deficient symptoms was leading to the diagnosis of Sjögren’s syndrome. In literature, there are other isolated case reports of sensory neuronopathy and autoimmune brachial diplegia associated with Sjögren’s syndrome.^{Reference Tominaga, Iizuka and Kaneko5} In a cross-sectional study done by Seeliger T et al., 44 patients with Sjögren’s syndrome and severe neuropathy with limb weakness were identified.^{Reference Seeliger, Prenzler and Gingele6} More than half of these patients fulfilled the European Federation of Neurological Societies criteria for Chronic Inflammatory Demyelinating Polyneuropathy. In a large case series by Mori et al., the clinicopathological features of 92 patients with primary Sjögren’s syndrome-associated neuropathy were summarized. The predominant neuropathic symptoms were found to be indicative of seven distinct forms of neuropathy, namely, sensory ataxic neuropathy, painful sensory neuropathy without sensory ataxia, multiple mononeuropathy, multiple cranial neuropathy, trigeminal neuropathy, autonomic neuropathy and radiculoneuropathy.^{Reference Mori, Iijima and Koike7} This case series provides compelling evidence of the propensity of Sjögren’s syndrome to manifest as plexopathy, thereby concomitantly broadening the phenotypic spectrum. We have summarized salient findings in a tabular form (Table 1).

Table 1.

Summary of salient clinical features in three cases

In our case series, patients presented with purely neurological symptoms and signs suggestive of lumbar and brachial plexopathies. In such cases, neurological manifestations may precede sicca symptoms and laboratory findings, and a continuous re-evaluation for objective xerophthalmia, xerostomia or parotid gland enlargement should be performed. Sjögren’s syndrome can have a multitude of neurological manifestations involving the peripheral and central nervous systems.^{Reference Barsottini, Moraes and Fraiman8} Literature is scarce regarding such presentations, and the evaluation and management have to be tailored to the individual. The limitation is short follow-up, and none of the patients developed systemic symptoms in this period.

Sjögren’s syndrome is a rare cause of lumbar and brachial plexopathies. Early diagnosis and management can lead to significant improvement and reduce morbidity. Neurological manifestations may ante-date sicca symptoms, and close follow-up is essential. Further studies are essential to know the long-term outcomes and optimum immunomodulation in such rare presentations.