Cryptogenic orginizing pneumonia

EPIDEMIOLOGY
The mean age at diagnosis is 50 to 60 years COP is rarely reported in children.
The incidence of cases is slightly higher among men than among women.

DIAGNOSTIC EVALUATION

COP is an inflammatory and fibroproliferative process characterized by intraalveolar fibroproliferation that is reversible

The results of laboratory tests are nonspecific in patients with COP, but inflammatory markers such as the erythrocyte sedimentation rate, C-reactive protein level, and leukocyte count are frequently elevated.

DIFFERENTIAL DIAGNOSIS

Pulmonary-function tests often show a restrictive ventilatory defect and a reduced diffusing capacity for carbon monoxide.

The manifestations of COP on a chest radiograph are typically distinctive, with bilateral opacities that are patchy or diffuse and consolidative or hazy, in the presence of normal lung volumes.The findings may be unilateral or bilateral. The lesions are found in all lung zones, with a slightly predominant subpleural and lower-lung- zone distribution.

THE MOST IMPORTANT MIMIC OF COP IS COMMUNITY-ACQUIRED PNEUMONIA

CLINICAL PRESENTATION

Symptoms are often subacute and can emerge over a period of several weeks to several months.

Common symptoms include dry cough and dyspnea (mild to moderate)

VARIANTS

Histopathological examination of a lungbiopsy specimen from a patient with COP reveals intraluminal plugs of loose connective tissue that involve alveolar spaces and alveolar ducts and may also involve bronchioles

Focal Organizing Pneumonia: is rare and patients are often asymptomatic

Fulminant disease: progressive clinical course of organizing pneumonia (requiring high-flow supplemental oxygen and progressing to mechanical ventilation).

other clinical processes:

  • eosinophilic pneumonia
  • alveolar hemorrhage
  • vasculitis
  • hypersensitivity pneumonitis
  • Pulmonary lymphoma and invasive mucinous adenocarcinoma

Cicatricial Organizing Pneumonia: In a subset of cases of organizing pneumonia, the airspaces are filled with loose, fibromyxoid connective tissue associated with the formation of intraluminal, dense eosinophilic fibrosis and preservation of the underlying lung architecture.

Acute Fibrinous and Organizing Pneumonia: rare alveolar filling disease, acute fibrinous organizing pneumonia, is characterized by a patchy distribution. This variant can be idiopathic or associated with other processes.

TREATMENT

Is empirical because no prospective randomized trial has been made.

A decision to start therapy and the choice of therapy depends on the severity of the clinical, physiological and radiologic abnormalities, and the rapidity of disease progression.

GLUCOCORTICOID THERAPY

THIS IS THE PREFERRED TREATMENT FOR PATIENTS WITH RESPIRATORY IMPAIRMENT DUE TO COP.

The usual starting dose is 0.5 to 1mg of prednisone per kg of body weight, given as a single oral dose in the morning for 2 to 4 weeks.
Depending of the clinical response, the dose is tapered to 0.25 mg per kg per day for 4-6 months of therapy.

Glucocorticoid therapy usually induces clinical improvement beginning withing 24 to 72 hours.
Patients have decreased symptoms, fallowed by resolution of radiologic findings withing 3 months after diagnosis.

Patients with severe or rapidly progressive disease and impending respiratory failure, high dose of methyl-
prednisolone IV with transition to oral administration once the patient's condition improves.

RELAPSE HAS BEEN REPORTED IN LESS THAN 25% OF CASES

IT CAN OCCURE WHEN TREATMENT IS TAPERED OR STOPPED TOO QUICKLY

IT CAN BE TRATED BY RESUMING OR INCREASING GLUCOCORTICOID TREATMENT

OTHER THERAPIES

Cytotoxic Therapy

Mycophenolate Mofetil and Other Agents

Macrolide antibiotics

PROGNOSIS

The prognosis and response to treatment for
patients with COP are generally excellent.

Patients with radiologic airspace opacities have better outcomes than thos with reticular opacities.

For patients hospitalized, the length of stay is usually less than 3 weeks with a rapid improvement

Death from COP occurs in less than 10% of cases and the cause is most times unrelated

INTEGRANTES: Agûero Sol, Gil Capra Ernestina, Gonzalez Sol