Sonozaki syndrome (pustulotic arthro-osteitis) causing anterior chest pain: a case report
Article information
Abstract
Sonozaki syndrome is an exceptionally rare chronic rheumatic disorder characterized by pustulosis on the palms and soles, as well as arthritis and osteitis. This syndrome belongs to the category of spondyloarthritis, which includes psoriatic arthritis. Pustules are concentrated on the palms and soles, whereas arthro-osteitis predominantly affects the sternoclavicular and costochondral joints. This report presents the case of a 32-year-old man with a 2-month history of worsening anterior chest wall pain and pustular eruptions on the palms and soles.
Introduction
Pustulosis of palms and soles (PPP) is also known as “pustulosis palmaris et plantaris” or “palmoplantaris pustulosis.” PPP is a chronic and recurring pustular skin lesion which is confined to the palms and soles [1]. Due to its similarity, it is often regarded as a subtype of psoriasis, but it only affects the palms and soles [2,3]. It typically occurs in patients aged 30 to 60 years and is equally common in males and females. It is common in Japan and the Scandinavian Peninsula, with a prevalence of 0.05% [4]. Inflammatory osteitis occurs in 10% to 30% of patients with PPP and is then called pustulotic arthro-osteitis or Sonozaki syndrome. This disease can induce chest pain and tenderness, especially in the costosternal joint, and it is often important to distinguish it from rib fractures and coronary artery disease. In this paper, we describe the diagnosis and treatment of a patient with Sonozaki syndrome, which has been treated in several hospitals due to chest pain, but successful resolution was not achieved.
Case
Ethical statements: This report was granted exemption from review by the Institutional Review Board (IRB) of Kosin Gospel Hospital (IRB No. 2024-06-008). The IRB waived the requirement for informed consent.
A 32-year-old male presented to our hospital with a 2-month history of lower chest wall pain and skin pustules. The chest wall pain was pleuritic and initially began in the left anterior chest wall, gradually spreading to the right anterior and posterior chest wall areas. He experienced temporary relief when he was treated at a local clinic, but the symptoms returned soon after. The pustules were localized to the palms and soles without pain or irritation. No relevant past or family history was noted. On physical examination, Vital signs were as follows: blood pressure of 110/70 mmHg, heart rate of 78 beats/min, respiratory rate of 20 breaths/min, and body temperature of 36.7 ℃. The electrocardiogram was normal. No abnormal findings were observed in the head and neck areas, but severe tenderness was palpated around the sternum. Multiple pustules with erythematous eruption were observed on the palms and soles (Fig. 1A, 1B), but no other skin lesions were found. Peripheral blood tests showed white blood cell count 13,700/mm3 (neutrophil 64.3%, lymphocyte 25.0%, monocyte 7.9%, eosinophil 2.3%, and basophil 0.5%), hemoglobin 14.1 g/dL, hematocrit 41.1%, and platelets 415,000/mm3. The urinalysis result was normal. Other pertinent results included elevated C-reactive protein level at 3.5 mg/dL, elevated erythrocyte sedimentation rate at 73 mm/hr, rheumatoid factor, anti-cyclic citrullinated peptide antibody, anti-nuclear antibody, and HLA-B27 gene results were all negative. Biopsies were conducted to obtain specimens from the palms and soles. It showed superficial perivascular dermatitis and subcorneal pustules (Fig. 2). No specific findings were observed in the radiologic tests. Bone scans, however, revealed isotope uptake at multiple levels of the costochondral junctions on both parasternal areas (Fig. 1C).
Numerous erythematous lesions with pustules, blisters, and thick yellow scales are evident on the palm (A) and sole (B). Bone scan with 99mTC shows increased uptake in the affected ribs (red arrows) (C).
Skin biopsy shows superficial perivascular dermatitis with subcorneal pustules (hematoxylin and eosin stain, ×200).
After a comprehensive history, physical examination, and relevant laboratory tests, trauma and other inflammatory diseases were ruled out, leading to a diagnosis of Sonozaki syndrome. Medications, such as prednisolone (5 mg/day), aceclofenac (200 mg/day), and esomeprazole (20 mg/day), were administered. After 2 weeks, the symptoms of the patient were completely resolved. Two months later, the patient returned with recurring chest wall pain and skin symptoms. The sulfasalazine (1,000 mg/day) was added to the same medication regimen as before. The symptoms subsequently improved, and he is currently scheduled for a follow-up without any medications.
Discussion
There are many conditions that can cause chest pain. When patients visit the department of thoracic and cardiovascular surgery with chest pain or discomfort, trauma, cardiovascular diseases, and pleural diseases are differentiated. Treatment becomes straightforward when there are clear causes such as fractures of bony thorax, pneumothorax, hydrothorax, and ischemic heart diseases. However, unfortunately, many patients do not know the exact cause of chest pain even after various tests. In such cases, most patients receive symptomatic treatment such as pain control and sometimes undergo psychiatric counseling. Symptomatic treatment may bring temporary improvement in symptoms. However, without addressing the underlying causes, the symptoms eventually recur. Patients who experience symptom recurrence or worsening often transfer to other hospitals, wasting time and sometimes missing the optimum timing for treatment. Specifically, as conditions like Sonozaki syndrome are rarely considered as a cause of chest pain, sharing of clinical experiences and reviews of the literature are important.
The possible etiologies of PPP include infection, trauma, smoking, and environmental factors. However, the exact causes are not known. According to a recent study, PPP patients have elevated levels of cytokines such as interleukin-17 and interleukin-22 in their serum and tissues, elevated T helper 17 cell counts, and depressed regulatory T cell counts, implying that an immunological imbalance could be an etiology of PPP, as well as psoriasis [5,6]. PPP may have a wide range of clinical manifestations, including pustules with surrounding erythema, pruritus, stabbing pain, and musculoskeletal symptoms [7-9]. When PPP is accompanied by arthro-osteitis, it is called pustulotic arthro-osteitis or Sonozaki syndrome, first reported by Sonozaki in 1981 [7,10]. Like psoriatic arthritis, Sonozaki syndrome is currently regarded as a type of seronegative spondyloarthritis [11].
Arthro-osteitis changes are localized to the sternum, clavicle, rib, spine, and pelvis and develop most frequently in claviculomanubrial joint [12]. However, this patient exhibited an unusual presentation with widespread pain at the bilateral costochondral junctions. In the case of PPP, arthritis is characteristically transient and non-erosive. Approximately 70% of arthro-osteitis patients experience skin lesions, and it usually takes 2 years after skin lesions occur before arthro-osteitis develops.
In our case, Sonozaki syndrome was diagnosed by finding chest tenderness on palpation, costochondritis on bone scan, and characteristic skin lesions on the palms and soles, as well as through excluding other diseases on the differential diagnosis.
Sonozaki syndrome typically follows a chronic, relapsing-remitting course, with treatments mainly focused on symptomatic management. Analgesics and nonsteroidal anti-inflammatory drugs are frequently used. When patients do not respond to these medications or experience a recurrence of symptoms, then glucocorticoid, colchicine, sulfasalazine, methotrexate, and cyclosporine can be used [10,11].
In our patient, sulfasalazine was added after a recurrence. The patient has been doing well without any further recurrences. If a recurrence occurs in the future, immunosuppressants may be considered. When a patient presents with unexplained chest pain, it is important not to focus solely on thoracic lesions. Instead, paying attention to various lesions, such as skin manifestations, can help in diagnosing and treating rare conditions like Sonozaki syndrome.
Notes
Conflicts of interest
No potential conflict of interest relevant to this article was reported.
Funding
None.
Author contributions
All the work was done by TYK.