65-year-old female patient with progressive mono neuritis multiplex and a history of pain in upper and lower limbs – 04/05/2022

Discussion of the case

The elderly female presented with rapidly progressive MM involving both upper and lower limbs. She had leucocytosis, normal inflammatory parameters, and a sural nerve biopsy showing vasculitis. Serum electrophoresis was suggestive of polyclonal gammopathy. Her clinical features were suggestive of vasculitis and polyarteritis nodosa or unclassifiable primary vasculitis. Whereas the rapid deterioration of mononeuritis and the patient's age indicate the probability of paraneoplastic syndrome. The incidence of fever and joint pain prior to neurological manifestations suggests the possibility of underlying infection. The researcher Finsterer has discussed a detailed approach to the management of MM.¹

Studies underscore the necessity to consider acute parvovirus B19 infection during the etiological assessment of MM.² Similarly, MM has been found to be associated with Epstein-Barr virus infection. The screening for various viral infections, most commonly HIV and hepatitis B/C, was negative in the current case.³

It is recommended to do a baseline assessment for malignancy in the elderly who present with acute onset mononeuritis. The disease often responds to steroid treatment, but it is usually refractory, and the patient may not have any clue about the malignancy.⁴ The disease is more commonly associated with lymphoma, myeloproliferative disorders, renal cell carcinoma, and lung and thyroid malignancy.⁵ However, in the present case, no underlying tumor/malignancy was reported.

Based on the observations, a clinical possibility of vasculitis was considered, and further workup included the assessment of ANCA, ANA, and complement levels. Her P-ANCA 2+ was positive, ANA was negative, and C3/C4 levels were normal. These findings suggested a possibility of ANCA-positive vasculitis. But clinical features were not suggestive of Wegener's granulomatosis. X-ray of the chest and the examination of the peripheral nervous system were normal. Anti-PR3 antibodies were found to be negative by immunoblot.

Considering the clinical classification criteria for ANCA-associated vasculitis, the present patient has biopsy-proven, small- and medium-sized vasculitis, which is ANCA positive.  Since the patient fulfils the criteria, the diagnosis can be concluded as ANCA-associated vasculitis.⁶

Final diagnosis

ANCA-associated vasculitis

Follow-up

Patient was managed with cyclophosphamide 500 mg bolus once in 15 days and a tapering dose of steroid. Recovery of neurological deficit was noted.

Learning points
·         In patients with mono neuritis multiplex, vasculitis along with a probable paraneoplastic syndrome, especially in a rapidly deteriorating neuropathy, should be considered.
·         The patient can be categorized as ANCA-associated vasculitis if there is associated documentation of vasculitis
·         It is preferable to exclude the possibility of associated malignancy in the elderly.

References

1. Finsterer J. Systemic and non-systemic vasculitis affecting the peripheral nerves. Acta Neurol Belg. 2009 Jun;109(2):100–13.
2. Lenglet T, Haroche J, Schnuriger A, Maisonobe T, Viala K, Michel Y, et al. Mononeuropathy multiplex associated with acute parvovirus B19 infection: characteristics, treatment and outcome. J Neurol. 2011 Jul;258(7):1321–6.
3. Corssmit EP, Leverstein-van Hall MA, Portegies P, Bakker P. Case Report Severe neurological complications in association with Epstein-Barr virus infection. J Neurovirol. 1997 Dec;3(6):460-4.
4.  Martin AC, Friedlander M, Kiernan MC. Paraneoplastic mononeuritis multiplex in non-small-cell lung carcinoma. J Clin Neurosci. 2006 Jun;13(5):595–8.
5. Gorson KC. Vasculitic neuropathies: an update. Neurologist. 2007 Jan;13(1):12-9
6. Jennette JC, Falk RJ, Bacon PA, Basu N, Cid MC, Ferrario F, et al. 2012 Revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides. Arthritis & Rheumatism. 2013 Jan 1;65(1):1–11.