Does serum angiotensin converting enzyme reflect intensity of alveolitis in sarcoidosis?

The Relationship Between Serum Angiotensin Converting Enzyme Level and the Decision to Escalate Treatment of Sarcoidosis

PURPOSE

We performed a retrospective analysis of a sarcoidosis cohort who had sACE obtained at their initial clinic visit, but the treating physician was blinded to the results. We examined the relationship between sACE and the treating physician's decision to escalate sarcoidosis treatment.

METHODS

Treatment was considered escalated if the prednisone dose was increased or if the prednisone dose was not changed but an additional anti-sarcoidosis drug was added or the dose was increased.

RESULTS

561 sarcoidosis patients were analyzed. The most common target organ was the lung (84%). Using a cut-off of > 82 units/L for an elevated sACE, 31/82 (38%) with an elevated sACE had treatment escalation whereas 91/497 (18%) had treatment escalation with a normal sACE (p < 0.0001). For the need of treatment escalation, a sACE (cut-off of > 82) had sensitivity 0.25, specificity 0.89, positive predictive value 0.38, negative predictive value 0.81. These results were not appreciably different using other sACE cut-off values such as 70, 80, 90, or 100. A multivariable logistic regression model that included demographics, the target organ, spirometry results estimated that sACE level and lower FVC were significantly associated with the likelihood of treatment escalation. These findings held when sACE > 82 replaced sACE level in the multivariable logistic regression model.

CONCLUSIONS

Although there was a strong correlation between sACE at the initial sarcoidosis clinic visit and subsequent treatment escalation of sarcoidosis, the predictive power was such that sACE is not adequately reliable to be used in isolation to make this determination.

Biomarkers in sarcoidosis

INTRODUCTION

Numerous biomarkers have been evaluated for the diagnosis, assessment of disease activity, prognosis, and response to treatment in sarcoidosis. In this report, we discuss the clinical and research utility of several biomarkers used to evaluate sarcoidosis. Areas covered: The sarcoidosis biomarkers discussed include serologic tests, imaging studies, identification of inflammatory cells and genetic analyses. Literature was obtained from medical databases including PubMed and Web of Science. Expert commentary: Most of the biomarkers examined in sarcoidosis are not adequately specific or sensitive to be used in isolation to make clinical decisions. However, several sarcoidosis biomarkers have an important role in the clinical management of sarcoidosis when they are coupled with clinical data including the results of other biomarkers.

Biochemical changes in sarcoidosis

Biochemical markers in sarcoidosis are closely related to the immunological events and the activity of inflammatory effector cells at sites of granuloma formation. The markers can be measured in serum, then reflecting whole body concentration, or in BAL fluid, then indicating activity in the lung. Only calcium and ACE serum levels have gained a proven value in the clinical field.

[Brucellosis with fatal endotoxic shock]

BACKGROUND

Brucellosis is a zoonosis with good prognosis in cases of early diagnosis. To make the diagnosis is still a problem today.

CASE REPORT

A 60-year-old butcher was admitted with undulating fever, sweats, arthralgia and weight loss. Further examination revealed hepatosplenomegaly with laboratory findings of a hepatitis and multiple focal liver lesions shown by abdominal ultrasound and CT. Histologically, these lesions corresponded to caseous granulomas. Diagnosis of brucellosis was confirmed by detection of brucella species in prolonged incubation in blood culture. After the beginning of antibiotic resistance-tested therapy with tetracycline and quinolones, an endotoxic shock occurred during the first 24 hours of treatment and the patient died after multiorgan failure with disseminated intravascular coagulation.

CONCLUSION

In cases of undulating fever with liver involvement, a brucellosis should be considered. Good teamwork of the internal, pathological and microbiological departments is necessary for early and correct diagnosis. This is the first report of human brucellosis in association with lethal endotoxic shock.

Serum angiotensin converting enzyme activity in chronic beryllium disease

Serum angiotensin converting enzyme (SACE) activity is used as a marker of sarcoidosis activity and severity, but in chronic beryllium disease (CBD) the studies of SACE give conflicting results. We examined SACE activity in 23 CBD patients, five patients with beryllium sensitization, and 25 beryllium-exposed control subjects. CBD patients underwent complete clinical evaluation, including physical examination, pulmonary function testing, exercise physiology testing, chest radiography, and bronchoscopy with bronchoalveolar lavage and biopsy. CBD SACE activity was systematically compared with these clinical markers of disease severity. Of CBD patients, 22% had elevated SACE activity. The test did not discriminate CBD patients from those in the beryllium-sensitized or beryllium-exposed groups. However, SACE activity in CBD correlated with the extent of pulmonary granulomatous inflammation as reflected by the symptom of breathlessness, the number of white cells in bronchoalveolar lavage (r = 0.44), the number of lavage lymphocytes (r = 0.58), the lavage lymphocyte percentage (r = 0.55), and the profusion of small opacities on chest radiograph (r = 0.41). The test-retest reliability of the assay was high (r = 0.84), as was the agreement between fresh and -70 degrees C frozen sera (r = 0.93). We conclude that SACE activity levels may reflect the extent of pulmonary granulomatous inflammation in CBD but that the test does not help discriminate disease from nondisease.

Bronchoalveolar lavage fluid angiotensin-converting enzyme in interstitial lung diseases

In this study we evaluated the disease specificity of bronchoalveolar lavage fluid angiotensin-converting enzyme (BALF-ACE), its correlation with cellular constituents of bronchoalveolar lavage fluid (BALF), and for sarcoidosis, with other proposed markers of disease activity. Furthermore, the question of the clinical value of BALF-ACE determinations in in interstitial lung diseases or any of its subgroups was addressed. The study population consisted of 222 patients, 69 with biopsy proven sarcoidosis, 3 with hypersensitivity pneumonitis, 4 with acute histoplasmosis, 27 with idiopathic pulmonary fibrosis (IPF), 4 with rheumatoid arthritis-related interstitial fibrosis, 9 with pulmonary drug toxicity, 16 with pulmonary malignancies, 26 with other parenchymal lung disease entities, and 30 in whom the final diagnosis remained indeterminate. Elevated BALF-ACE concentrations were seen in all diagnostic categories. In sarcoidosis BALF-ACE levels correlated well with lavage lymphocyte counts (r = 0.49; p less than 0.0001), in contrast to IPF where they correlated well with lavage neutrophil counts (r = 0.51; p less than 0.007). The correlation of BALF-ACE and serum-ACE was significant. In sarcoidosis the mean BALF-ACE level was lower for patients with Stage-I chest roentgenographic patterns (0.664 U/L), compared to those with Stage II (1.112 U/L) and Stage III (1.083 U/L). It was concluded that elevated BALF-ACE levels are not specific for sarcoidosis. The correlations of BALF-ACE levels with different cellular constituents of BALF suggest a different cellular origin of BALF-ACE. In sarcoidosis BALF-ACE levels correlate well with other proposed markers of disease activity and seem to reflect pulmonary activity better than serum ACE.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchoalveolar lavage cell counts as a predictor of short term outcome in pulmonary sarcoidosis

Sixty seven patients with biopsy proven pulmonary sarcoidosis were prospectively studied to determine whether single point bronchoalveolar lavage cell counts were a useful indicator of functional outcome and whether repeated lavage helped in management. The mean follow up period was 25 (range 13-37) months. No patient was having corticosteroid treatment at the time of initial bronchoalveolar lavage. "High intensity alveolitis" (lymphocyte count greater than or equal to 28%) was present at the initial lavage in 42 patients. These patients showed a significant improvement in their pulmonary function and chest radiographs over the follow up period whereas patients with "low intensity alveolitis" did not. Of the 42 patients with high intensity alveolitis, 31 had chronic sarcoidosis (duration over two years, mean 80 months). These patients showed a significant improvement in FVC but not in TLCO. Corticosteroids resulted in greater functional and radiological improvement in the patients with high intensity alveolitis than in those with low intensity alveolitis. Repeat bronchoalveolar lavage in 34 patients, mean 8.4 months after the original lavage, showed a weak inverse relation between a reduced lymphocyte count and change in forced vital capacity and isotope uptake on a gallium scan. These correlations were too weak to make repeated cell counts useful in management. Our results suggest that high intensity alveolitis may be a favourable prognostic factor for lung function in pulmonary sarcoidosis, even in patients with chronic disease, but that repeat lavage adds little to the management of the individual patient.

Diagnostic aspects of angiotensin converting enzyme in pulmonary sarcoidosis

Angiotensin converting enzyme (ACE) has been measured in 102 biopsy-proven sarcoid patients, 70 patients diagnosed by clinical and radiological methods and 74 nonsarcoid patients as controls. The distributions of the various groups have been examined, and the effects of stage of disease, disease activity and prednisone treatment have been evaluated. Receiver operating characteristic (ROC) curves have been established for ACE, and the appropriateness of various statistical procedures is discussed. We have not discerned any effect of stage of sarcoidosis or of extent of disease activity on ACE values. The ROC curves suggest an upper limit of normal of about 50 U/L for our assay, and a sensitivity of 63% and specificity of 93%, yielding predictive values of 93% for a positive result and 74% for a negative result, with a likelihood ratio of 3.6. The results are discussed in the context of other work on ACE and in relation to the more invasive procedures of bronchoalveolar lavage and Gallium scan.

Biochemical markers in sarcoidosis

The clinical course of sarcoidosis is varying and unpredictable. Once the diagnosis has been made, the clinician needs simple tests to detect and predict remission or progression, to determine whether treatment is effective or not, and to assess the clinical activity of the disease. Sarcoidosis is a multisystem disease, but the lungs are almost always involved. Traditionally, the clinical management has therefore included chest X-rays and lung function studies. Extrapulmonary lesions have been followed in different ways. Sensitive and reproducible biochemical tests would be helpful in evaluating the clinical course of patients with sarcoidosis, if they measure functions related to the granulomatous inflammation. This review will deal with measurements of serum and urinary calcium, and 1,25-dihydroxyvitamin D. The usefulness of single and serial determinations of lysozyme, angiotensin converting enzyme, beta 2-microglobulin, collagenase, carboxypeptidase and glucuronidase in serum, bronchoalveolar lavage fluid, and other biological fluids will be discussed.