acute fibrinous and organizing pneumonia ( afop ) was first described by beasley et al . in 2002 as a condition characterized by alveolar damage , eosinophilic pneumonia , and organizing pneumonia .
the features that distinguish it histologically are the presence of intra - alveolar fibrin balls , absence of usual hyaline membranes and eosinophils and many foci of fibroblastic activity .
it has been described in almost all age groups with associations including autoimmune disease and connective tissue , drugs , occupational , and environmental exposures and other infectious agents .
they are usually two forms of this illness , a severe form which leads to rapid respiratory failure and a subacute form which has a much better prognosis .
there is no specific treatment though immunosuppressant and steroids produce good results in patients with sub - acute afop .
the chest radiograph findings of afop are almost identical to those seen in cryptogenic organizing pneumonia , consistent with migratory , patchy , diffuse , alveolar opacities with bilateral , and peripheral distributions .
a 42-year - old female was admitted with complaints of dry cough of 5 days , high - grade fever since 15 days , generalized malaise and progressive worsening shortness of breath since 5 days .
no known chemicals , fumes or occupational or allergen exposure . upon examination , she was dyspneic , blood pressure of 110/70 mmhg and had fever of 103 f. she had a respiratory rate of 32/min , heart rate of 120 beats / min .
she had no icterus , edema , clubbing , rash , skin lesions , cervical lymphadenopathy , or joint swelling .
her arterial blood gas ( abg ) analysis revealed ph of 7.47 , pco2 of 41 mmhg , and po2 of 39 mmhg .
chest radiographic findings showed inhomogeneous bilateral opacification in lower lung zones . the rest of the laboratory tests , including liver function test , kidney function test , coagulation profile , urine examination , etc .
work up of anti - nuclear antibodies , angiotensin converting enzyme , dsdna antibodies , antinuclear and cytoplasmic antibodies , rheumatoid arthritis factor , extractable nuclear antigen profile , and anti - phospholipid anti bodies were negative .
she was initially treated with noninvasive ventilation , oxygen therapy , antibiotics such as combination antibiotic regimen with pipercillin - tazobactam with and clarithromycin .
high - resolution computed tomography ( hrct ) thorax revealed bilateral diffuse confluent consolidation in lower lung zones [ figure 1a  c ] .
bronchoscopy followed by bronchoalveolar lavage ( bal ) was performed ( gene xpert real - time pcr ) .
transbronchial lung biopsy was performed from the right lower lobe , biopsy report of which came out to be afop [ figure 1d and e ] .
she was treated with 40 mg prednisolone twice daily along with bronchodilators and oxygen therapy .
her abg also improved significantly with po2 at 92 mmhg and her saturation at 95% .
she was initially on high flow oxygen mask which came down to minimum level and eventually she did not require any oxygen therapy after 5 days of steroid therapy initiation .
( a ) axial and ( b ) cornal computed tomography through lungs : geographical distribution of widespread consolidation with ground glass opacities and septal thickening in both lungs .
( c ) axial computed tomography taken after 15 days after treatment : resolution of large component of organizing consolidation with residual ground glass opacities and mild septal thickening .
( d and e ) intra - alveolar fibrin in the form of  fibrin balls  without formation of hyaline membranes ( h and e , 100 )
afop has been reported in all age groups with average age being 62 years originally described by beasley et al .
it has been reported that afop may occur as an idiopathic variety or in association with clinical conditions , including collagen vascular diseases , drug reactions , occupational or environmental exposures , as well as various infections .
retrospective follow - up of these patients shows two varieties of progression . a subacute variety and a severe variety which usually leads to respiratory failure and the prognosis of the severe variety is not promising . on average , severe form of afop
this variety seems to resemble cryptogenic organizing pneumonia ( cop ) in terms of prognosis and recovery following corticosteroid treatment .
afop has been described with many other conditions in the past while twelve reported cases were idiopathic .
therefore , there could be an association between autoimmune disease and afop . in our case ,
there was no evidence of malignancy or any other factors known to be related with pneumonia .
however , lung biopsy revealed that the patient has unusual histological pattern that was identified as afop . nevertheless , it is important to note that sub - acute forms of this disease seem to be mistaken for cop .
therefore , histological diagnosis is essential for distinguishing the two through ct - guided or bronchoscopic biopsy .
the most commonly used methods to obtain a tissue sample include video - assisted thoracoscopic biopsy and a ct - guided biopsy .
diagnosis of afop in indian case reports has been achieved through ct guided biopsy followed by treatment of the disease by prednisolone .
she required intensive care support for 5 days eventually being discharged home after 10 days of hospitalization .
by this study , we suggest that afop should be taken into consideration and differential diagnosis of severe acute pneumonias with no significant co - morbidities . diagnosis is mostly biopsy proven , and treatment through corticosteroids is quite promising .
 acute fibrinous and organizing pneumonia ( afop ) is a rare disease characterized by bilateral basilar infiltrates and histological findings of organizing pneumonia and intra - alveolar fibrin in the form of  fibrin balls .  here , we report a 43-year - old female with complaints of fever , dry cough , and shortness of breath with hypoxemia . 
 high - resolution computed tomography thorax revealed diffuse confluent consolidation in bilateral lung zones . 
 bronchoscopy and transbronchial biopsy revealed features of afop . 
 with prednisolone treatment , there was an improvement in her condition . 
 afop is a rare disease and should be taken into consideration and differential diagnosis of severe acute pneumonias with no significant comorbidities . 
Introduction
Case Report
Discussion
Conclusion
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