Acute fibrinous and organizing pfneumonia: two case reports and literature review

Identification of novel TTN gene variant in a patient exhibiting severe dilated cardiomyopathy co-occurring with acute fibrinoid organizing pneumonia

OBJECTIVES

Dilated cardiomyopathy (DCM) is often hereditary, with 20% to 40% of nonischemic cases showing familial linkage, yet genetic testing is underused. This report describes an unreported pathogenic nonsense variant in the Titin (TTN) gene (NM_001267550.2:c.92603G>A) in a 24-year-old man with severe DCM and acute fibrinoid organizing pneumonia, highlighting a unique cardiopulmonary pathology.

METHODS

We conducted detailed gross, histopathologic, immunophenotypic, and exome-based DNA sequencing analysis in the workup of this case. We also included the patient's clinical and radiologic findings in our study.

RESULTS

With rapid clinical deterioration and complex comorbidities, including substance abuse and psychiatric conditions, which precluded transplantation, the patient's cardiac function progressively worsened. Autopsy findings included extreme cardiomegaly, biventricular hypertrophy, and acute and chronic pericarditis. Significant pulmonary pathology consistent with acute fibrinoid organizing pneumonia was also noted. Molecular testing confirmed a deleterious maternally inherited TTN variant that was absent in the sibling of the proband and the extant medical literature, highlighting its rarity and significance.

CONCLUSIONS

This case contributes to the ongoing body of work on the impact of TTN variants on DCM. It suggests a potential link between genetic variants and complex cardiac injury patterns, emphasizing the need for further investigation into the interplay between cardiomyopathy and pulmonary pathology.

An autopsy case of acute fibrinous and organizing pneumonia with periorbital MRSA cellulitis and rheumatoid arthritis

This case report details a 78-year-old male with periorbital Methicillin-resistant Staphylococcus aureus (MRSA) cellulitis whose condition rapidly deteriorated despite treatment. An autopsy confirmed acute fibrinous and organizing pneumonia (AFOP), revealing fibrin ball formation and organizing pneumonia. While both idiopathic and secondary AFOP cases often exhibit bilateral consolidation on CT, our patient presented with ground-glass opacities, which are frequently associated with secondary AFOP. Notably, secondary AFOP, linked to higher mortality, can result from various factors. In this case, well-controlled rheumatoid arthritis and prolonged oral medication use suggest bilateral periorbital MRSA cellulitis as a significant factor. The study underscores AFOP's diagnostic challenges and the necessity for further research on effective treatments.

A rare pulmonary manifestation of Crohn's disease: Acute fibrinous and organizing pneumonia presenting as multifocal nodules

Acute Fibrinous and Organizing Pneumonia (AFOP) is a rare pulmonary disease, and it has not been recorded in literature as a pulmonary manifestation of Crohn's disease. A 22-year-old individual with an extensive history of Crohn's disease presented to the hospital initially for hematochezia and diarrhea. Computed tomography of her abdomen and pelvis showed multiple pulmonary nodules bilaterally. The patient did not report cough, sputum production, or dyspnea. Autoimmune and infectious workup were overall unremarkable. A CT-guided percutaneous biopsy of a peripheral lung nodule was performed showing features consistent with AFOP. The patient was ultimately treated with a long taper of prednisone and Ustekinumab for Crohn's disease. Follow-up CT-chest showed interval reduction and improvement in lung nodules, which correlated with better control of the patient's Crohn's disease. Pulmonary manifestations of IBD are varied, including pleural disease, bronchiectasis, and organizing pneumonia. Bronchiolitis obliterans organizing pneumonia has been described more frequently in patients with ulcerative colitis compared to Crohn's. Pulmonary nodules are a rare manifestation of IBD and often tend to be granulomatous or necrobiotic. AFOP is a rare entity with no previously reported association with IBD. Secondary AFOP can be caused by autoimmune diseases, drug reactions, infections, or radiation. Treatment of AFOP is usually immunosuppression by glucocorticoids.

A case report: Acute fibrinous and organizing pneumonia

RATIONALE

Acute fibrinous and organizing pneumonia (AFOP) is a rare acute or subacute interstitial lung disorder characterized by the deposition of fibrin within the alveoli and organizing pneumonia with a patchy distribution. The clinical features of AFOP are nonspecific, and it is often misdiagnosed as pneumonia, cancer, tuberculosis, or other lung disorders.

PATIENT CONCERNS

In this case report, a 58-year-old woman presented with chest tightness, shortness of breath, cough and sputum. A chest CT scan showed multiple patchy shadows in both lungs. She was initially diagnosed with community-acquired pneumonia. Her purified protein derivative skin test was positive, but sputum was negative for acid-fast bacilli.

DIAGNOSES

AFOP was diagnosed by bronchoscopic lung biopsy and histopathology.

INTERVENTIONS

Following AFOP diagnosis, all anti-infective drugs were discontinued, and replaced by methylprednisolone and prednisone.

OUTCOMES

After 1 week of treatment with methylprednisolone 40 mg daily, the patient chest CT and clinical symptoms improved. After 1 month, the patient symptoms had demonstrated dramatic improvement and CT scan revealed complete absorption of lesions in both lungs. After 5 months of follow-up, the patient symptoms completely disappeared.

LESSONS

Acute AFOP is an uncommon lung condition with poor prognosis; hence, early diagnosis and identification are particularly important. Definitive diagnosis requires histopathological findings. Currently, there is no unified treatment guideline for AFOP, and treatment must be tailored based on the etiology and severity of each individual patient disease. Subacute AFOP shows a good response to corticosteroid treatment.

Update on cryptogenic organizing pneumonia

Cryptogenic organizing pneumonia (COP) is a form of idiopathic interstitial pneumonia that results from the pulmonary reaction to various unidentified injuries. Secondary organizing pneumonia is diagnosed when the triggering factor has been identified; it is mainly caused by infections, toxic substance exposure, drugs, connective tissue diseases, malignancies, autoimmune diseases, bone marrow, or organ transplantation, and radiotherapy. There has been an increase in the number of reports of drug-induced organizing pneumonia (OP). New biological therapies, interferon, monoclonal antibodies, anti-interleukin antibodies, and PD1/PDL-1 inhibitors may induce this specific pulmonary reaction. The classical form of COP is usually subacute and does not manifest as severe disease. Patients maintain sufficient respiratory function, and treatment with steroids is usually effective. Several specific forms of OP (e.g., the cicatricial variant or acute fibrinous type) have distinct clinical and histological features, require higher doses of immunosuppressive drugs, and have a worse prognosis. In the era of administering steroid-sparing therapies for the treatment of interstitial lung diseases, connective tissue dases, and other conditions, it is important to emphasize this type of therapy for patients with COP.

Two methods of lung biopsy for histological confirmation of acute fibrinous and organizing pneumonia: A case report

BACKGROUND

Acute fibrinous and organizing pneumonia (AFOP) is a rare, noninfective lung disease, histologically characterized by a patchy distribution of intra-alveolar fibrin “balls” and organizing pneumonia. The clinical manifestations of AFOP are nonspecific. Diagnosis depends on pathology. Surgical lung biopsy is optimal for tissue sampling to diagnose AFOP. However, many patients have no tolerance to the operation, including mentally and physically. There is still no standard therapy for AFOP and the methods remain controversial. Therefore, further clinical attention and discussion are warranted.

CASE SUMMARY

A 53-year-old woman presented with fever, cough and dyspnea for 15 d. Anti-infective therapy was ineffective. Chest computed tomography showed bilateral patchy consolidation, especially in the lower lobes. We performed both ultrasound-guided transbronchial lung biopsy and ultrasound-guided percutaneous fine needle puncture at different lung lesion locations. Both samples supported the diagnosis of AFOP. The patient had a good clinical course after treatment with methylprednisolone, and no side effects of steroids.

CONCLUSION

Percutaneous needle biopsy combined with transbronchial lung biopsies may be a good choice in the absence of surgical biopsy. Methylprednisolone alone is effective in the treatment of idiopathic AFOP.

Relapse of idiopathic acute fibrinous and organising pneumonia 12 years after successful treatment with corticosteroids

Acute fibrinous and organising pneumonia (AFOP) is a rare form of interstitial lung disease. It is a pathological diagnosis sharing similarities to organising pneumonia, diffuse alveolar damage and eosinophilic pneumonia, however, is histologically distinct, characterised by intra-alveolar fibrin deposition ('fibrin balls') and associated organising pneumonia. AFOP was first described in 2002, only 150 cases have been reported since. While it has been described in association with infection, autoimmune disorders, connective tissue diseases, drugs, environmental exposures and organ transplant, it can also be idiopathic in nature. AFOP follows an acute course with potential rapid fulminant respiratory failure, or a subacute trajectory with a more favourable prognosis. Corticosteroids are commonly prescribed to induce remission. While cases of relapse of AFOP during weaning or cessation of steroids have been described, there are no published cases of remote relapse of AFOP. We describe a case of idiopathic AFOP, which recurred after 12 years of good health.