Erythema nodosum and the risk of tuberculosis in a high incidence setting

Clinicopathological Characteristics Related to Etiologies of Erythema Nodosum: A 10-Year Retrospective Study

Background

Erythema nodosum (EN) is the most common panniculitis associated with a wide variety of conditions. Updated studies regarding the clinicopathological manifestations related to etiologies of EN and its prognosis are limited.

Objective

We aimed to explore the clinicopathological features in relation to the etiologies of EN and determine characteristics of disease recurrence and its predictive factors.

Methods

A total of 169 patients with biopsy-proven EN or septal panniculitis from January 2008 to September 2018 were retrospectively reviewed. Patients were classified as either idiopathic or secondary EN. Patients’ general information, clinical manifestations, investigations, and recurrence of EN were recorded. The details on histopathological findings were reviewed by a blinded dermatopathologist.

Results

The mean age at diagnosis of EN was 40.6 ± 17.3 years. The majority of patients (85.2%) were female. Idiopathic EN was found in 62.7% of patients. Tuberculosis (23.8%) and drugs (23.8%) were the leading causes of secondary EN. In univariate logistic regression analysis, lesions on upper extremities (p = 0.018), fever (p = 0.003), clinical lymphadenopathy (p < 0.001) favored secondary EN. Histopathologically, the presence of focal peripheral lobular panniculitis with eosinophils was linked to idiopathic EN (p = 0.03). However, multivariable logistic regression analysis failed to demonstrate factors associated with secondary EN. Recurrence was found in 46.6% of patients with no identifiable predictive factors.

Conclusion

Although no clinical risk factors were associated with the etiology of EN, the histopathological presence of eosinophils in focal peripheral lobular panniculitis suggested idiopathic EN.

Erythema Nodosum: A Practical Approach and Diagnostic Algorithm

Erythema nodosum is the most common form of panniculitis and is characterized by tender erythematous nodules mainly in the lower limbs on the pretibial area. The exact cause of erythema nodosum is unknown, although it appears to be a hypersensitivity response to a variety of antigenic stimuli. Although the etiology is mostly idiopathic, ruling out an underlying disease is imperative before diagnosing primary erythema nodosum. Erythema nodosum can be the first sign of a systemic disease that is triggered by a large group of processes, such as infections, inflammatory diseases, neoplasia, and/or drugs. The most common identifiable causes are streptococcal infections, primary tuberculosis, sarcoidosis, Behçet disease, inflammatory bowel disease, drugs, and pregnancy. We propose a diagnostic algorithm to optimize the initial work-up, hence initiating prompt and accurate management of the underlying disease. The algorithm includes an initial assessment of core symptoms, diagnostic work-up, differential diagnosis, and recommended therapies. Several treatment options for the erythema nodosum lesions have been previously reported; nevertheless, these options treat the symptoms, but not the triggering cause. Making an accurate diagnosis will allow the physician to treat the underlying cause and determine an optimal therapeutic strategy.

Skin manifestations in spondyloarthritis

Spondyloarthritides (SpA) like psoriatic arthritis, axial spondyloarthritis/ankylosing spondylitis, reactive arthritis and inflammatory bowel disease (IBD)-associated SpA can present with characteristic skin manifestations. These SpA-associated skin disorders may precede joint involvement, reflect a loss of efficacy of a current systemic treatment or can even be treatment associated. Cutaneous manifestations in SpA not only add additional morbidity with physical impact but also impose a psychosocial burden on affected patients. Psoriasis (PsO) - the main skin disease in SpA - has a variety of clinical presentations, including plaque-type PsO, inverse PsO, guttate PsO, erythrodermic PsO, nail PsO and pustular types. SpA associated with IBD presents with neutrophilic and granulomatous skin disorders, including pyoderma gangrenosum, hidradenitis suppurativa and cutaneous Crohn's disease. Reactive arthritides has a favourable prognosis and may feature keratoderma blenorrhagicum or balanitis circinatum as typical skin manifestations. Immunologically, SpA-associated skin diseases share interleukin (IL)-17 and IL-23 dysregulation but show distinctive genetic and immunological profiles. Therefore, they vary in their treatment responses to targeted therapies with biologicals or small molecules. In this review, we highlight the clinical presentation of skin manifestations in SpA and discuss therapeutic approaches in this interdisciplinary field.

A case of extra pulmonary tuberculosis misdiagnosed as granulomatosis with polyangitis: Presenting with occipital condylar syndrome

Sri Lanka is a tuberculosis (TB) prevalent country with an incidence of 8886 cases in 2016 of which 30% were extra pulmonary tuberculosis (EPTB). These figures may be an underestimation, considering the diagnostic challenge of EPTB due to its diverse presentations and difficulty in microbiological confirmation. Here we describe a case of EPTB which was first diagnosed as granulomatosis with polyangitis when he presented with fever, anorexia, wasting, large joint pains, cervical pain, erythema nodosum, high inflammatory markers with strongly positive Mantoux reaction and, necrotizing granulomatous lymphadenitis in the cervical region. Immunosuppression with methotrexate 15 mg weekly and prednisolone 30 mg daily, achieved resolution of symptoms and the inflammatory markers. After about 4 months on tailing off prednisolone, he developed fever, anorexia, wasting and worsening occipital pain which evolved in to occipital condylar syndrome causing hypoglossal nerve palsy. With the aid of serial radiological, histopathological and bacteriological investigations, he was eventually diagnosed to have EPTB involving the left base of the skull with upper mediastinal lymphadenitis. This case highlights the importance to have a high index of suspicion to diagnose EPTB, especially in a country with a high prevalence of TB and to revise the diagnosis with a close follow up to avoid disastrous consequences associated with misdiagnosis.

Erythema Nodosum: A Manifestation of Salmonella Infection

Erythema nodosum is a delayed-type hypersensitivity reaction with an unknown trigger in the majority of cases. It is characterized by the development of erythematous tender nodules on the shins. Septal panniculitis without vasculitis is a characteristic histopathological finding. We report the case of a 26-year-old woman who presented with a four-day history of an erythematous swollen left lower limb. She was treated with intravenous clindamycin for suspected cellulitis. However, her symptoms persisted. Punch biopsy revealed findings consistent with erythema nodosum. Two days later, she developed colicky abdominal pain associated with non-bloody diarrhea. Stool culture yielded Salmonella enterica serotype enteritidis. Two days after discharge, she presented again with a right breast abscess for which she underwent incision and drainage along with antibiotic therapy. After discharge, she was symptom-free with complete resolution of the cutaneous lesions. The presented case is unique as it had multiple clinical manifestations of Salmonella infection including erythema nodosum, diarrhea, and presumably a breast abscess. It should be kept in mind that gastrointestinal symptoms are not necessarily the initial presentations of Salmonella infection.

Erythema nodosum

BACKGROUND

Erythema nodosum can be associated with a number of systemic diseases. There is, however, a paucity of information in the pediatric literature on this condition. The purpose of this article is to familiarize pediatricians with the evaluation, diagnosis, and treatment of erythema nodosum.

DATA SOURCES

A PubMed search was completed in Clinical Queries using the key terms "erythema nodosum".

RESULTS

Clinically, erythema nodosum presents with a sudden onset of painful, erythematous, subcutaneous nodules mainly localized to the pretibial areas. Lesions are usually bilateral and symmetrical, ranging from 1 to 5 cm in diameter. Erythema nodosum may be associated with a variety of conditions such as infection, medications, sarcoidosis, pregnancy, inflammatory bowel disease, vaccination, autoimmune disease, malignancy, and miscellaneous causes. The condition is idiopathic in approximately 50% of cases. The diagnosis is mainly clinical with biopsy reserved for atypical cases. To evaluate for the underlying cause, some basic laboratory screening studies are worthwhile in most cases and include a complete blood cell count, erythrocyte sedimentation rate and/or C-reactive protein, throat swab culture, antistreptococcal O titers, and a chest radiograph. Other tests should be individualized, guided by the history and physical examination results. Most cases of erythema nodosum are self-limited and require no treatment. Bed rest and leg elevation are generally recommended to reduce the discomfort. Nonsteroidal anti-inflammatory drugs are the first-line treatment for pain management.

CONCLUSIONS

As erythema nodosum is often a cutaneous manifestation of a systemic disease, a thorough search should be performed to reveal the underlying cause.

Erythema nodosum as sign of primary tuberculosis

Erythema nodosum is a panniculitis associated with numerous diseases such as infections, inflammatory diseases, tuberculosis or can be idiopathic. We here report a case of a woman with erythema nodosum and reactive arthritis who was subsequently diagnosed with tuberculosis. A high level of suspicion and a thorough clinical and laboratory investigation of the patient presenting with erythema nodosum is required, in order to detect a possible systemic underlying condition.

Examination of the Microbial Spectrum in the Etiology of Erythema Nodosum: A Retrospective Descriptive Study

Even though infections are the most common cause of erythema nodosum (EN), only certain microorganisms take the great interest such as streptococci in knowledge. Our aim was to examine the frequency and type of infections in EN, to determine the characteristics of patients with an infectious etiology, and to discuss the role of these microbes in EN pathology in the context of their interactions with humans. Charts of 81 patients with EN who were seen between 2003 and 2017 were retrospectively reviewed. Identified etiological factors were classified into three groups: infectious, noninfectious, and idiopathic. While there were no significant demographic and clinical differences between the infectious and idiopathic groups, systemic symptoms (p = 0.034) and the number of EN lesions (p = 0.016) were significantly lower; the mean erythrocyte sedimentation rate was significantly higher (p = 0.049), but the mean aspartate aminotransferase value was significantly lower in the infectious group compared to the noninfectious group (p = 0.019). Besides streptococci, many other microbes, including the ones living on and inside us, were identified in the etiology of EN. There is a need for large-scale prospective studies involving control groups for a better understanding of the microbial immunopathology of EN.