Immunoglobulin G4-Related Disease Masquerading an Epidural Spinal Cord Tumor

Mass: The Conundrum in Spine

Introduction

Immunoglobulin (Ig)G4-related disease belongs to a rare compilation of conditions in rheumatology and may involve a multitude of organs. Amidst the central nervous system (CNS) presentation, involvement of spinal cord is rarer still.

Case Report

Case 1: A 50-year-old male came with chief complaints of tingling sensation over both soles since 2 months associated with lower back ache and gait disturbance in the form of spastic gait. X-rays of spine were suggestive of a growth at the level of D10-D12 compressing the spinal cord with no focal sclerotic/lytic lesions, and MRI dorsolumbar spine showed dural tail sign. The patient underwent excision of dural mass, and histopathology revealed majority of plasma cells positive for IgG4. Case 2: A 65-year-old female came with complaints of cough, shortness of breath, and fever on and off since 2 months. No history of hemoptysis, purulent sputum, weight loss. On examination: There were bilateral rhonchi in the left upper zone. MRI spine showed focal erosion with soft-tissue thickening at the right paravertebral region extending from D5-9. The patient underwent surgery (fusion D6-8 and ostectomy D7 posterior rib resection D7 right side) with the right pleural biopsy and transpendicular intracorporal biopsy D7. Histopathology was compatible with findings of IgG4 disease.

Conclusion

IgG4 tumors presenting in CNS itself is rare and rarer in spinal cord. Histopathological examination is central to diagnose and prognosticate the disease further as IgG4-related disease manifestations may recur without proper treatment.

Immunoglobulin G4-Related Spinal Intramedullary Inflammatory Pseudotumor: A Case Report and Literature Review

Immunoglobulin G4-related disease (IgG4-RD) is an autoimmune disease that affects several organs. An inflammatory pseudotumor is a histologically proven benign tumor-like lesion that most commonly involves the lung and orbit. It is rare in the central nervous system, but rarest in the spinal canal. In this report, we present a case of IgG4-related intramedullary spinal inflammatory pseudotumor, along with a literature review. A 29-year-old male was transferred to the Department of Neurosurgery of Lanzhou University Second Hospital with progressive quadriparesis after numbness and weakness in both lower limbs for 50 days. Enhanced magnetic resonance imaging (MRI) of the spine revealed an isointense signal on T1-weighted images and a hyperintense signal on T2-weighted images from an enhanced mass located at the thoracic vertebrae region, for which a schwannoma was highly suspected. Then, a posterior median approach was adopted. The lesion was resected. The patient received further glucocorticoid after the diagnosis of an IgG4-related inflammatory pseudotumor was established, and the patient's symptoms improved, such as quadriparesis and lower limb weakness. This case highlights the importance of considering IgG4-related inflammatory pseudotumor as a differential diagnosis in patients with lesions involving the spinal intramedullary compartment and lower limb weakness when other more threatening causes have been excluded. IgG4-related inflammatory pseudotumor is etiologically unclear and prognostically unpredictable, and imaging may not help establish the diagnosis of IgG4-related inflammatory pseudotumor due to its resemblance to malignant tumors, and total resection might not be warranted. Glucocorticoid and surgery are usually the first-line treatments used.