Introduction
Mononeuropathy multiplex (MM) is a painful neuropathy involving the
sensory and motor peripheral nerves in two separate nerve areas
simultaneously [1, 2].
The differential diagnoses associated with MM include a wide range of
systemic disorders such as diabetes mellitus, vasculitis, amyloidosis,
systemic lupus erythematosus (SLE), viral infections such as AIDS
(acquired immunodeficiency syndrome), hepatitis, parvovirus B19,
multiple compression neuropathies and paraneoplastic syndromes
[3-6]. One possible, albeit rare, cause is lymphoma [7].
Intravascular lymphoma(IVL), a rare B-cell lymphoma, involves an
aggressive intravascular overgrowth of neoplastic B-lymphocytes in small
to medium-sized vessels [8]. The resulting deficits in vascular
supply to organs produce a range of systemic and neurologic symptoms
that often overlap with those of other diseases, especially
vasculopathies[9]. The most common symptoms include skin lesions and
fever/chills. The majority of patients with intravascular lymphoma who
develop neurologic symptoms show central nervous symptoms such as
cognitive or motor deficits [9]. A systematic review of reported
cases estimated that the peripheral nervous system was involved in a
minority of 9.5% of patients who experienced some degree of involvement
as a late finding discovered only after diagnosis[9].
Diagnosing intravascular lymphoma is challenging because it is rare and
it presents with a wide variety of symptoms[11]. Moreover, its
diagnosis relies on clinical suspicion and tissue biopsy [10]. On
the other hand, this type of non-Hodgkin lymphoma is lethal within a
year unless diagnosed and treated early [11]. These issues highlight
the importance of early accurate diagnosis and treatment and the role of
a high index of suspicion for this life-threatening disease in patients
presenting with symptoms suggesting vascular involvement [11-13].
Since intravascular lymphoma and its neurologic manifestations are rare;
and the disease course is short with a fatal outcome, the study of their
clinical course is limited to case reports and case series[11].
Previous case reports have reported patients with intravascular lymphoma
presenting with peripheral neuropathy; However, MM as the primary
presentation is extremely rare [7, 14-18]. Previously reported
patients were diagnosed in post-mortem autopsies after an initial
misdiagnosis of vasculitis [18, 19].
We report a case in which MM was the core manifestation of intravascular
large B-cell lymphoma(IVLBCL) and was diagnosed based on a nerve biopsy.