Introduction

Sweet's Syndrome (SS) or acute febrile neutrophilic dermatosis is a systemic inflammatory disorder characterized by fever, leukocytosis, and tender erythematous skin lesions. This disorder typically involves multiple organs; but pulmonary involvements is rare. The classical manifestations of pulmonary involvement in SS are lung infiltrates, pleural effusion, and bronchiolitis obliterans organizing pneumonia (BOOP). Treatment with steroids shows dramatic improvement. Colchicine and immunosuppressant agents may also be used in treatment.

Case Report

A 68- year old white male was referred to the pulmonary consultation service for evaluation of left hilar mass. He had history of adult - onset diabetes mellitus (AODM) and atherosclerotic heart disease (ASHD) requiring permanent pacemaker insertion 7 years ago and a 50 pack-year cigarette smoking history. He denied night sweats, and weight loss. There was a history of an episode of respiratory tract infection five months ago for which he was treated with oral antibiotics for ten days. He has had dyspnea on exertion for many years, but no recent increase has been noted.

 This patient has also had history of recurrent erythematous rash associated with nodular plaque lesions and pustules on forearms, hands, and neck for last 7 years. Skin biopsy was done in past and diagnosis of Sweet's Syndrome was established and was treated with Prednisone 40 mg/day as recommended by dermatology service.

 He also reported history of "spots in the lungs" in the past and review of his old records revealed reports of pulmonary infiltrates at different sites at different times with no pulmonary symptoms. Extensive workup was done several times including cultures of sputum, blood, and urine, thoracentesis, and bronchoscopy. None of tests revealed any infectious, granulomatous or malignant etiology of his pulmonary infiltrates.

Past medical history was consistent with peptic ulcer disease (PUD), ASHD, Diabetic Melllitus with neuropathy.  No history of tuberculosis (TB),    sarcoidosis,  or any fungal disease.

His medications include Insulin, Lasix, Digoxin, Nitropaste, Fluphenazine, Nortryptiline, Lisinopril, Diltiazem, Pentoxifiline, Sucralfate, and Clonidine.

He was divorced and worked as a taxi driver. He had a history of alcohol abuse in the past.  His mother has a history of ASHD.

Upon examination, the patient appeared chronically ill appearing in no acute distress. The temperature was 99.2 F., the blood pressure 120/76 ,  the heart rate 76 per minute with regular rhythm, and the respiratory rate 18 breaths per minute. The skin showed erythematous purple rash in both hands and forearms with  multiple nodular lesions of 4 to 10 mm in size and pustules. Few of such lesions also were present on the neck. The head and neck examination revealed pupils equally reactive to light. Few teeth were present with poor oral hygiene. The neck was supple with no jugular venous distension, or adenopathy. The chest exam disclosed hyperinflation, with decreased breath sound in both sides, no crackles or wheezes. The auscultation of the heart showed normal heart sounds without gallop or murmurs. The abdomen was soft, no hepato or splenomegaly, no masses, bowel sounds were normal. The extremities showed  no joint swelling, clubbing, or pedal edema. On neurological examination, the patient was alert, oriented times 3, decreased sensations to fine touch and pain in both hands and feet.

The laboratory results revealed a white blood cell count of 10.6 k/mcl, Hemoglobin 15g/dl, Hematocrit 43.5% , Platelets 409 k/mcl, Glomerular filtration rate 89 ml/min, Sodium 135 mEq/L., Potassium 4.6mEq/L., Chloride 101 mEq/L., Bicarbonate 26 mEq/L., Glucose 94 mg/dl, BUN 24 mg/dl, Serum creatinine 9 mg/dl, Ca 9.1 mg/dl., Urine analysis was unremarkable, Erythrocyte sedimentation rate  was 5mm/h.

Pulmonary function testing disclosed an FVC of 4.12 L (90% predicted)  and FEV1 2.4 L (68% predicted). The chest X-ray revealed bilateral hilar infiltrates. Bronchoscopy showed no endobronchial lesions, but purulent secretions were noted coming from the left lower lobe superior  segment.

The microbiological analysis of the secretions was negative for bacteria, acid-fast bacilli, and fungus. A fine needle aspiration of the lung infiltrate showed pulmonary  macrophages, but no malignant cells. 

Discussion

One half century after Dr. Sweet described the Acute Febrile Neutrophilic Dermatosis syndrome, there have been 41 cases reported of pulmonary involvement and here we are reporting the 42nd case.

This is a 67 year-old man, who was referred to us for an evaluation of a left hilar abnormality, having no respiratory complaints. His past medical history revealed a recurrent erythematous, violaceous, plaque-forming, nodular rash involving hands, forearms, and neck that every time it would flare up, it was accompanied by a fever. A retrospective analysis of his chest radiographs disclosed evidence of recurrent ill defined infiltrates concurrent with his febrile episodes and reactivations of his cutaneous disorder that he had been experiencing for the previous 6 years. These infiltrates would leave as sequelae linear fibrotic strands. During these episodes, the patient had been asymptomatic from respiratory standpoint; but his fever and dermatological lesions would respond dramatically to corticosteroid therapy.

          Skin biopsy showed the classical dermal neutrophilic  infiltration without vasculitis, compatible with SS. Fiberoptic bronchoscopy revealed purulent secretions coming out of the superior segment of the left lower lobe and a fine needle lung aspiration disclosed alveolar macrophages and neutrophils. The stains, cultures, and cytologies from both procedures turned out to be all negative.

In our literature review we obtained a total of 42 patients including ours, 19 of them were men and 23 women. The average age was 54.36. Seven  patients ( 17% ) have AML. Three patients had anemia. Five patients had a cardiovascular disease. Twelve patients had unremarkable underlying conditions. With chest X-ray 18 patients showed only unilateral infiltrate. From the 42 patients one patient was treated and improved with colchicine. Forty patients had been treated with steroids, 29 patients improved on steroid alone without any recurrence or complications. Five patients improved on combination between steroid and other medications. Five patients improved on steroid then died for a different condition. One patient improved with steroid but had a recurrence.

          We conclude that based on the following facts: 1) cyclic concomitance of skin and lung diseases 2) sterile nature of lung lesions 3) response to corticosteroid therapy; that we are reporting the forty-second case of pulmonary involvement in Sweet's syndrome.   

Table1a

Previously Reported Cases of Sweet’s Syndrome with Pulmonary Involvement

Table1b

Previously Reported Cases of Sweet’s Syndrome with Pulmonary Involvement

Table1c

Previously Reported Cases of Sweet’s Syndrome with Pulmonary Involvement

A chest X-ray revealed bilateral hilar infiltrates (Fig.1).

Figure 1

Bilateral parahilar infiltrates on chest x-ray

Conclusion

Based on the significant evidence of pulmonary involvement in this case and the other reported cases we conclude that Sweet's Syndrome or so called Acute Febrile Neutrophilic Dermatosis does involve the lung, it is frequently encountered in association with granulocytic cell proliferation or immunological conditions, it does respond to corticosteroid therapy but it has high recurrence rate and promotes a great deal of pulmonary fibrosis which ultimately may lead patients to respiratory insufficiency and death, therefore it should be considered in the differential diagnosis of lung infiltrates.