The three conditions that make up Felty Syndrome (FS) are rheumatoid arthritis (RA), splenomegaly (enlarged spleen), and neutropenia (low white blood cell count).¹ It mostly affects those who have had rheumatoid arthritis for a long time, and because of neutropenia, it can make them more vulnerable to infections.² Although the precise origin of Felty Syndrome is uncertain, rheumatoid arthritis-related immune system hyperactivity is thought to be a contributing factor.² 

Immunosuppressive drugs and supportive therapies are usually used in combination for effective management.¹ This article discusses the role of physical therapy in FS.

Introduction

Rheumatoid arthritis, neutropenia, and splenomegaly are the hallmarks of the uncommon extra-articular presentation of seropositive rheumatoid arthritis known as felty syndrome, alternatively referred to as Chauffard-Still-Felty illness. Dr Augustus Felty initially described FS in 1924.⁴ Baseline data indicates a relationship with specific human leukocyte antigen (HLA) subtypes, while the exact cause is yet unknown. 

Neutropenia is signalled by the formation of antibodies against granulocyte colony-stimulating factor (G-CSF). There might be obvious autoantibodies. This abnormality may also be seen in T-cell entities. Neutropenia causes severe or recurring infections, particularly those affecting the skin and respiratory system, which are especially problematic. Therapy aims to prevent diseases and raise the white blood cell count.³

Approximately, 10 cases per 100,000 individuals are expected to have FS in 1-3% of RA cases.⁴ The probability of Felty syndrome appears to be decreasing with the advancement of RA pharmacotherapy, which includes increased use of biologics and methotrexate (MTX). 

The true prevalence of this condition is extremely low. FS typically manifests 16.1 years following the onset of RA, and patients who have family members with a history of RA are more susceptible. Furthermore, among individuals with Felty syndrome, there is a higher correlation between RA and HLA DR4. Similar to RA, the illness strikes women three times as frequently as men, manifests in middle age, the mean age being 50-70 years and disproportionately affects white people as opposed to non-white people.^3,4

Pathophysiology

It's unclear exactly what causes Felty syndrome, and there could be other contributing factors. It is believed to involve immunological processes that are both humoral and cellular, which help to cause abnormalities in neutrophil survival and propagation that lead to neutropenia. The amelioration of neutropenia following splenectomy can be used to support the theory that increased sequestration from splenomegaly and inadequate generation from cytotoxic lymphocytes infiltrating the bone marrow are the causes of neutropenia.³

IgG Anti-G-CSF antibodies were discovered in 73% of patients with Felty syndrome in a case-control study. These antibodies were linked to low neutrophil counts and an elevated serum G-CSF level. This implies that neutropenia in Felty syndrome patients may be caused by a high G-CSF level and apathy of myeloid cells to G-CSF. Neutrophil sequestration results from autoantibodies in FS binding to deaminated histones and extracellular chromatin traps for neutrophils. Felty syndrome and chronic large granular lymphocyte leukaemia may share a pathologic connection because of their comparable clinical presentations and shared HLA-DR4 aetiology. Elevated levels of Fas ligand and other autoimmune disorders like RA are common in patients with LGL leukaemia, indicating a similar pathogenic process.³

Clinical manifestations

Patients with FS typically have an infection because they don't normally have any symptoms. Skin and respiratory infections are the most prevalent forms. Numerous patients present with additional extra-articular symptoms like Hepatomegaly (68%), lymphadenopathy (42%), Sjogren syndrome (48%), pleuritis (22%), rheumatoid nodules (74%), peripheral neuropathy (14%), and leg ulcers (16%). There may also be systemic signs, such as fever and weight loss. Clinical examinations typically reveal the spleen to be palpable. Variceal haemorrhage may also result from idiopathic non-cirrhotic portal hypertension in certain individuals.³ Among these other indications and symptoms include swollen, painful, and stiff joints in the hands, feet, and arms, exhaustion, thrombocytopenia, or anaemia.⁴

FS’s diagnosis includes physical examinations like feeling for enlarged lymph nodes, palpating of an enlarged liver, palpating of an enlarged spleen, and looking for joints showing signs of RA, laboratory tests such as rheumatoid factor (RF) presence, elevated erythrocyte sedimentation rate (ESR), elevated serum immunoglobin levels, low white blood cell count (less than 1500/mm3), etc. as well as diagnostic exams, like computed tomography (CT) scans, radionuclide studies, and ultrasounds can all show signs of splenomegaly. Bone marrow aspiration and biopsy can be utilised to better examine haematopoiesis and rule out the involvement of other haematological or non-haematological illnesses in the bone marrow.⁴

This syndrome's uncommon occurrence and inconsistent clinical appearance make diagnosis difficult. A multidisciplinary approach to complete management that incorporates the skills and knowledge of physicians, advanced care practitioners, nurses, chemists, and other health professionals is required for felty syndrome in addition to astute clinical observation and diagnostic acumen.³

Physical therapy interventions

Physical therapists oversee pain, fatigue, and activity moderation as part of the symptom management protocol for patients with FS. If FS is not present, RA should be managed with bed rest, physical activity, heat treatments, gold salts, NSAIDS (nonsteriodal anti-inflammatory drugs), and penicillamine. Patient-centred physical therapy must be used for patients with severe joint engagement, with an emphasis on fatigue management and balancing daily activities. 

The patient and the physical therapist should both be involved in this self-care regimen. Joint protection strategies (education, splints, assistive devices, orthotics), functional activities/ADL training, stretching, aerobic exercise, resistance training, patient education, lifestyle management, and pain-reduction modalities (heat, massage, ice, ultrasound, electrical stimulation) can all help achieve these goals.⁴

• Aerobic exercises and strength training

Moderate to intense aerobic exercise, either on land or in the water, should be done three times a week for 30 to 60 minutes each day. Depending on the patient's level of weariness and pain, the intensity must be modified. It is recommended to engage in moderate-to-intense strengthening activities two to three times a week, utilising a variety of gear or bodyweight workouts. During these workouts, joint protection is essential, with a focus on larger joints and good mechanics.⁴ 

• Heat and cold therapy

In the treatment of arthritis, cold/hot modalities are frequently employed, with the application of heat in the chronic stages and cold in the acute episodes. Heat relieves pain, relaxes tense muscles, and increases the suppleness of the periarticular structure. It is advised to use thermotherapy for 10–20 minutes each day, such as superficial hot packs, infrared radiation, paraffin, fluidotherapy, or hydrotherapy. Patients with reduced vascular circulation and sensory impairments should be handled carefully. 

In dynamic joints where an increase in heat is undesirable, cold application is recommended. Inflamed joints create enzymes that break down cartilage, and these enzymes are influenced by temperature. When superficial heat is applied, intra-articular temperature rises, and when cold is applied, it falls. Elevated intra-articular temperature, however, does not improve radiologic progression or clinical outcome.⁵

• Ultrasound and electrical stimulation

One popular technique for treating RA pain in patients is transcutaneous electrical nerve stimulation (TENS). According to studies, the TENS with the greatest frequency offers the longest-lasting analgesia up to eighteen hours. After a week of application, TENS also reduces discomfort and strengthens hand grip. Using TENS for postoperative pain management lowers the demand for analgesic medications and hospital stays. Interferential current is also useful for reducing pain and swelling and enhancing range of motion.⁵

• Patient education

Patients with RA frequently experience sociopsychological variables such as depression connected to their work and poor social relationships. Patients are educated on medication therapy, physiotherapy, orthoses, psychological coping mechanisms, self-relaxation, diets, and regular exercise through a multidisciplinary education program that includes rheumatologists, orthopedicians, physiotherapists, psychologists, and social workers. Improvements in clinical prognosis, psychosocial interaction, and disability are reported by participants. Patients should be informed about the possibilities for physical therapy by clinics.⁵

Conclusion

Felty Syndrome (FS) is a rare but serious disorder that develops as a result of long-term rheumatoid arthritis (RA), and is distinguished by the triad of RA, splenomegaly, and neutrophilia. Because of the low white blood cell count, the syndrome makes people more susceptible to infections, hence comprehensive therapy is essential. Physical therapy plays an important part in this care since it addresses both the physical and functional issues that FS presents.

Physical therapy can help decrease symptoms including joint pain, stiffness, and fatigue that are typical in FS by providing personalised interventions. Aerobic workouts, strength training, and flexibility exercises are critical for preserving mobility, increasing strength, and preventing additional joint degradation. Furthermore, techniques such as heat, cold therapy, and electrical stimulation alleviate pain and improve joint function. Physical therapists can teach patients about joint preservation methods, energy conservation, and the benefits of living an active lifestyle within their capabilities.

Furthermore, patient education and self-management measures are essential for empowering people to take charge of their health. By utilising these therapeutic modalities, physical therapy not only improves physical function but also adds to a higher quality of life by reducing disability and assisting patients in effectively managing the chronic aspect of Felty Syndrome.