Key findings:

The abstract reports a case of polyarteritis nodosa (PAN) primarily presenting with neuropathy in the context of hepatitis B virus (HBV) infection. It underscores the importance of considering PAN in patients with nonspecific symptoms and HBV positivity, highlighting the need for comprehensive diagnostic evaluation and tailored management strategies.

What is known and what is new?

Polyarteritis nodosa (PAN) is a known small and medium vasculitis often associated with nonspecific symptoms and occasionally with hepatitis B virus (HBV) infection. However, this abstract presents a case highlighting PAN's clinical manifestation primarily as neuropathy in the context of HBV infection, emphasizing the need for heightened clinical suspicion and targeted management strategies.

What is the implication, and what should change now?

The case highlights the importance of considering polyarteritis nodosa (PAN) in patients presenting with nonspecific symptoms, particularly neuropathy, and a history of hepatitis B virus (HBV) infection. It underscores the need for comprehensive evaluation and prompt management, including antiviral therapy, immunosuppression, and plasma exchange, to effectively address HBV-related PAN and prevent complications.

Polyarteritis nodosa [PAN] is a rare systemic inflammatory necrotizing vasculitis of small and medium sized arteries. It can manifest as fever, abdominal pain, weight loss, neuropathy, arthritis and renal failure [1]. The non-specific symptoms and rarity of the PAN cause delay in diagnosis and when left untreated has poor prognosis. About 7% of the patients with PAN are hepatitis B surface antigen positive. The vasculitis in HBV associated with PAN is proposed to be due to deposition of viral circulating immune complexes [2]. We present a case of HBV associated with PAN diagnosed and managed in a tertiary care institute of north India

A 25 years old male patient presented in a tertiary care institute with paraesthesia of all extremities of 2-month duration followed by weakness of extremities associated with skin rash. Weakness was distally predominant with no symptoms suggestive of proximal or truncal weakness, bowel and bladder involvement. On examination of upper limbs partial ulnar claw hand with hypothenar, thenar wasting and wrist drop was there. Macular rash was present on the forearm [Picture 1 and 2]. On lower limb examination there was thinning of both limbs and cutaneous ulcer along with macular rash was present [Picture 3 and 4]. Muscle power was reduced in wrist, MCP, ankle and metatarsophalangeal joints. Ankle reflexes were absent and planters were mute. All sensory sensations were lost in the area supplied by the median and ulnar nerve in hands, similarly in distal lower limbs. Nerve conduction studies were suggestive of sensorimotor axonal polyneuropathy. Patient was evaluated on the line of mononeuritis multiplex.  On laboratory evaluation there was anemia, leukocytosis and thrombocytosis. Hepatic markers [HBsAg and HBeAg] were positive with high HBV viral load. Possibility of vasculitis was kept after ruling out all other etiologies. In contrast with enhanced CT [CECT] abdomen there were multiple tiny aneurysms in bilateral intraparenchymal renal arteries consistent with medium vessel vasculitis. On nerve biopsy there was healed vasculitis with secondary axonopathy and demyelination with small and large fibre loss. Final diagnosis was hepatitis B associated polyarteritis nodosa [PAN]. Patient was started on Tenofovir and prednisolone, and received 12 cycles of plasma-pharesis. Patient improved clinically, able to do his routine activities and walking without support.

Picture 1 and 2: Upper limb of the patient showing macular rash on forearm and wrist drop. There is partial ulnar claw hand with Hypothenar muscle wasting

Picture 3 and 4: Lower limbs of the patients showing cutaneous ulcers, macular rash with thinning of limbs

PAN is a systemic necrotizing vasculitis and it primarily affects medium-size arteries. It was first described by Kussmaul and Meier in 1866. It can be primary or secondary to certain infections, the most common being HBV. It affects all racial groups, ages and genders [3]. The etio-pathogenesis implicated to PAN is immune complex deposition leading to vascular injury. There is a close relationship between PAN and Hepatitis B infection but immune complexes are rarely found in the vessel walls of PAN [4]. Treatment of PAN is a challenge and several immunosuppressive and antiviral regimens have been used with varying success. Conventional therapy of PAN consists of immunosuppression with steroids, cyclophosphamide and methotrexate, whether or not in combination with plasma exchanges [5]. Immunosuppressive regimens have proven efficacy against the symptoms of vasculitis but perpetuate chronic HBV infection. Antiviral treatment was introduced for HBV related PAN. The case discussed was diagnosed with Hepatitis B virus associated with PAN and managed with Tenofovir, Prednisolone and plasmapheresis. 

1. McMahon, Brian J., et al. "Hepatitis B-Associated Polyarteritis Nodosa in Alaskan Eskimos: Clinical and Epidemiologic Features and Long-Term Follow-Up." Hepatology, vol. 9, no. 1, 1989, pp. 97-101. DOI: 10.1002/hep.1840090116.

2. Trepo, Christian G., et al. "The Role of Circulating Hepatitis B Antigen/Antibody Immune Complexes in the Pathogenesis of Vascular and Hepatic Manifestations in Polyarteritis Nodosa." Journal of Clinical Pathology, vol. 27, no. 11, 1974, pp. 863-868. https://doi.org/10.1136/jcp.27.11.863.

3. Hernández-Rodríguez, José, et al. "Diagnosis and Classification of Polyarteritis Nodosa." Journal of Autoimmunity, vol. 48, 2014, pp. 84-89. https://doi.org/10.1016/j.jaut.2014.01.029.

4. Leib, Edward S., Carl Restivo, and Harold E. Paulus. "Immunosuppressive and Corticosteroid Therapy of Polyarteritis Nodosa." The American Journal of Medicine, vol. 67, no. 6, 1979, pp. 941-947. https://doi.org/10.1016/0002-9343(79)90634-X.

5. Guillevin, L., et al. "Polyarteritis Nodosa Related to Hepatitis B Virus. A Retrospective Study of 66 Patients." Annales de Médecine Interne, vol. 143, 1992. https://europepmc.org/article/med/1363769.