Tanmay S. Panchabhai

Lymphocytic Interstitial Pneumonia

Lymphocytic interstitial pneumonia (LIP) is a rare lung disease on the spectrum of benign pulmonary lymphoproliferative disorders. LIP is frequently associated with connective tissue diseases or infections. Idiopathic LIP is rare; every attempt must be made to diagnose underlying conditions when LIP is diagnosed. Computed tomography of the chest in patients with LIP may reveal ground-glass opacities, centrilobular and subpleural nodules, and randomly distributed thin-walled cysts. Demonstrating polyclonality with immunohistochemistry is the key to differentiating LIP from lymphoma. The 5-year mortality remains between 33% and 50% and is likely to vary based on the underlying disease process.

When the picture is fragmented: Vitamin B12deficiency masquerading as thrombotic thrombocytopenic purpura

Thrombotic thrombocytopenic purpura (TTP) has high mortality and necessitates prompt recognition of microangiopathic hemolytic anemia (MAHA) and initiation of plasmapheresis. We present a challenging diagnostic workup and management of a 42-year-old man who presented with anemia, thrombocytopenia, and schistocytes on peripheral smear, all pointing to MAHA. Plasmapheresis and steroid therapy were promptly initiated, but hemolysis continued. Further workup showed megaloblastic anemia, severe Vitamin B12deficiency, high iron saturation, and absent reticulocytosis, none of which could be explained by TTP. Severe Vitamin B12deficiency can lead to hemolytic anemia from the destruction of red cells in the marrow that have failed the process of maturation. However, this should not cause thrombotic microangiopathy. Previous reports of B12deficiency presenting with MAHA and a TTP-like manifestation have identified acute hyperhomocysteinemia as a missing link between B12deficiency and MAHA, so this possibility was further explored. Our patient similarly had significantly elevated serum homocysteine levels, confirming this suspicion of Vitamin B12deficiency. Vitamin B12replacement led to normalization of the elevated levels of homocysteine, the disappearance of schistocytes on the peripheral smear, and resolution of the microangiopathic hemolysis, thereby confirming the diagnosis. It is pertinent that intensivists not only know the importance of early recognition and treatment of TTP but are also familiar with rare conditions that can present in a similar fashion.

Plugs of the Air Passages: A Clinicopathologic Review

Although mucus is a normal product of the tracheobronchial tree, some diseases of the respiratory tract are characterized by unusually thick (inspissated) forms of mucus that accumulate within the airways. These are known as mucus plugs. The pathologic composition of these plugs is surprisingly diverse and, in many cases, correlates with distinctive clinical, radiologic, and bronchoscopic findings. The best-known conditions that involve mucus plugs are allergic bronchopulmonary aspergillosis, plastic bronchitis, and asthma. Other lung diseases occasionally associated with plugs within the airways include Aspergillus tracheobronchitis, hyper-IgE syndrome, exogenous lipoid pneumonia, pulmonary alveolar proteinosis, and chronic eosinophilic pneumonia. In this review, we describe and illustrate the bronchoscopic, pathologic, and imaging findings in respiratory disorders characterized by mucus plugs or plugs composed of other similar materials. Recognition of the characteristic appearance and differential diagnosis of mucus plugs will hopefully facilitate diagnosis and management of these diseases.

Pulmonary Mycobacterial Spindle Cell Pseudotumor: A Report of 3 Cases Including a Practical Approach to Histopathologic Recognition of This Unusual Entity:

Mycobacterial spindle cell pseudotumor (MSP) is a rare benign spindle cell lesion containing acid-fact mycobacteria. These lesions are most commonly identified in the lymph nodes, skin, spleen, or bone marrow of immunocompromised patients and only rarely involve the lungs. We report 3 cases of pulmonary MSP, which include 2 patients who are known to be HIV-positive. The histopathological diagnosis of MSP in the lung lends itself to many challenges due to its rare incidence and its spindled tumor-like appearance. The differential diagnosis is broad and includes both benign and malignant entities. We highlight the importance of the clinical context in which these lesions typically present and the morphologic spectrum of features seen, and we offer a practical approach to the workup of pulmonary mycobacterial pseudotumor. Appropriate recognition of this entity should lead to an accurate diagnosis of a treatable benign condition despite the clinical presentation often favoring malignancy.

Atrial Fibrillation and Pulmonary Venous Electrical Conduction Recovery After Full Surgical Resection and Anastomosis of the Pulmonary Veins. Insights From Follow-Up and Ablation Procedures in Lung Transplant Recipients

OBJECTIVESnThe authors report their experience with atrial fibrillation (AF) rates and ablation findings in lung transplant recipients.nnnBACKGROUNDnPulmonary venous (PV) conduction recovery accounts for most failed atrial fibrillation (AF) catheter ablation procedures. Lung transplantation involves full surgical resection and replacement of the recipients PVs withxa0donors PVs, which may represent the ultimate PV ablation.nnnMETHODSnThey followed 755 consecutive lung transplant recipients categorized based on transplant status (unilateralxa0vs. bilateral) and pre-transplant AF.nnnRESULTSnIn patients without pre-transplant AF (nxa0= 704), late AF (beyond 6 months after transplant) occurred in 2.5%xa0and 3.3% of unilateral or bilateral lung transplants, respectively. In patients with pre-transplant AF (nxa0= 51), AF recurred in 19.4% and 25.0% of bilateral and unilateral transplants, respectively. In a subset of patients who underwent left atrial ablations after transplant for recurrent refractory AF (nxa0= 8), PV conduction recovery across the surgical anastomoses lines was observed in 22 of 26 previously disconnected PVs. Conduction recovery was observed inxa0≥1 vein in all but 1 patient. Re-isolation of the veins with additional substrate modification/flutter ablations successfully restored and maintained sinus rhythm in 7 of 8 patients.nnnCONCLUSIONSnIn lung transplant recipients who undergo full surgical resection of the PVs, a prior history of AF wasxa0associated with late AF, regardless of whether patients underwent single or bilateral lung transplantation. PVxa0conduction recovery still occurred and was observed in most patients who underwent left atrial ablation procedures for recurrent AF.

Acute ischemic optic neuropathy with extended prone position ventilation in a lung transplant recipient.

Prone position ventilation (PPV) improves mortality in severe acute respiratory distress syndrome (ARDS), but outcomes following its use in lung transplant recipients are not known. We report the case of a 42-year-old Caucasian man who presented with severe ARDS from Bordetella pertussis, 5 years after bilateral sequential lung transplant for cystic fibrosis. He was managed with PPV for 22 days and had a prolonged ICU stay complicated by hypoxic ischemic optic neuropathy leading to blindness. Since his discharge from the ICU 6 months ago, his FEV1has recovered to 47% predicted compared to his pre-ICU peak FEV1of 85% predicted, suggesting recovery of lung function. This is the first report of optic nerve damage and vision loss in patients undergoing PPV. Our report also suggests that, in appropriately selected lung transplant recipients, severe hypoxemia could potentially be managed with prone ventilation.

Complications of Lung Transplantation: A Roentgenographic Perspective

Lung transplantation is now an established treatment for a broad spectrum of end-stage pulmonary diseases. According to the International Society for Heart and Lung Transplantation Registry, more than 50,000 lung transplants have been performed worldwide, with nearly 11,000 lung transplant recipients alive in the United States. With the increasing application of lung transplantation, pulmonologists must be cognizant of common complications unique to the postlung transplant period and the associated radiologic findings. The aim of this review is to describe clinical manifestations and prototypical radiographic features of both common and rare complications encountered in lung transplant recipients.

A 42-Year-Old Woman With Abnormal Chest CT Scan and Chylous Ascites

A 42-year-old white woman presented to the pulmonary clinic for evaluation of abnormal chest imaging. Twenty years prior to presentation, she was noted to have an abnormal chest radiograph during a routine preemployment evaluation. A subsequent bronchoscopy was nondiagnostic. She was followed up with annual imaging, which demonstrated little or no progression of her disease. She remained symptom free throughout this period. A year before her visit to the pulmonary clinic, she developed abdominal discomfort and was found to have ascites. Subsequently, she underwent three paracenteses with analysis revealing chylous fluid. She was a nonsmoker without a history of exposures or travel.

Lung Transplant Recipient with Pulmonary Alveolar Proteinosis

Pulmonary alveolar proteinosis (PAP) is a progressive lung disease characterized by accumulated surfactant-like lipoproteinaceous material in the alveoli and distal bronchioles. This accumulation is the result of impaired clearance by alveolar macrophages. PAP has been described in 11 solid organ transplant recipients, 9 of whom were treated with mammalian target of rapamycin inhibitors. We report a case of a lung transplant recipient treated with prednisone, mycophenolate mofetil (MMF), and tacrolimus who ultimately developed PAP, which worsened when MMF was replaced with everolimus.

Development of Squamous Cell Carcinoma After Pulmonary Aspergillosis in the Native Lung of a Lung Transplant Recipient: A Case Report

Lung transplant recipients have a significant incidence of posttransplant lung nodules. Such nodules can occur from various etiologies, both in the lung allograft or in the native lung. They most commonly originate from infections, such as Pseudomonas or Aspergillus species, or from posttransplant lymphoproliferative disorder. Lung cancer is challenging to diagnose in a native lung, especially with an underlying fibrotic disease. We present a case of a 75-year-old woman who presented with classic clinical features of pulmonary aspergillosis in the native right lung with idiopathic pulmonary fibrosis 5 years after left-sided single-lung transplant. She required a right lower lobectomy and antifungal treatment with isavuconazonium sulfate and inhaled amphotericin. A persistent right upper lobe lung nodule was noted during surveillance imaging and was initially presumed to be recurrent Aspergillus infection; however, growth of the nodule and change in its characteristics prompted additional examination. A navigational bronchoscopic biopsy was positive for squamous cell carcinoma. Her options for stage IIIA squamous cell carcinoma were limited to chemotherapy with paclitaxel and carboplatin plus radiation. Although initial surveillance scans showed adequate tumor response, metastatic squamous cell carcinoma was found in the liver 6 months later. She was eventually transitioned to palliative care. This case highlights the importance of a high index of suspicion for examination of nodules in the native lung of lung transplant recipients, even in cases of a known diagnosis, owing to the high morbidity and mortality associated with primary lung cancer in this population.