CBI 3: 52 year old man with hemoptysis: WEGENER’S GRANULOMATOSIS
Initial Case Presentation
Chief Complaint:
Martin Smith is a 52 year old male mechanic who comes to urgent care complaining of coughing up blood since the previous evening.
Diff Dx:
- TB/Cocci
- Lung Cancer
- Mesothelioma
- PE
- Vasculitis (Wegener’s)
- Pneumonia
- Trauma
- Goodpasture’s
- Laryngeal Cancer
- CHF
- Lupus
HPI (Pertinent):
- Bright red blood in small amounts continuously last night and this morning. ½ cup total.
- Began 10-14 days ago with dyspnea, NPC, and 7 days of blood streaked sputum
- + night sweats
- 35 pack/year smoking history
- X wt loss, chest pain, hematemesis, chest pain, orthopnea, wheezing, easy bruising/bleeding, hematuria.
ROS (Pertinent):
- Rash on fingers noted 1 month ago
- Mild myalgias x1 month
Physical (Pertinent):
- Pulse Ox: 90%
- RR: 24
- Crackles over both lung fields, prominent at bases
- Guiac +
Lab (Pertinent):
- CXR: Bilateral opacities with alveolar filling patterns
- Elevated WBC (PMNs) & Platelets
- Low CO2, PaCO2, PaO2 (mild respiratory alkalosis)
- Elevated BUN/Creatitine (10:1 intrarenal), ESR (inflammation), CRP
- Hematuria w/casts (glomerulonephritis), proteinuria
Learning Issues
- Red rash- Steve
- Goodpasture’s- Jen
- Lupus-Karen
- Wegener’s- Nick
- Obstructive VS Restrictive Lung Dz (lung function tests and causes)-
- Summarize quantifying renal function (calculate GFR, renal plasma clearance, afferent and efferent arterioles)-Raji
- Antibiotics review-Mike
Friday Session-Presentations
Palmar Rash
- Purpura: RBC’s extravasate into superficial space. Palpable VS non-palpable.
- Wegner’s skin manifestations: Ulcers, purpura, vesicles, hemorrhage, and papules.
- Goodpasture’s skin manifestations: None
- SLE skin manifestations:
- Malar facial rash
- Discoid pattern rash
- Subacute cutaneous: Recurrent (papulosquamous or annular) rashes on extremities on face, extremities, and trunk.
SLE
- Systemic autoimmune disease seen mostly in young women with higher incidence in African and Hispanic Americans.
- Etiology: Antibodies to many different self tissues form. HLA DR3 and DR4 predispose people to developing SLE.
- Pathophysiology: Type III hypersensitivity due to immune complex deposition in the tissues with activation of complement.
- Clinical Criteria:
- Malar/discoid rash
- Photosensitivity
- Arthritis
- Hematologic disorders
- Renal disorder (subendothelial wire-loop lesions, mesangial hyperplasia)
- Serositis
- Fever
- Libman-Sacks endocarditis (mitral vegetations)
- Cause of Death: Infection and renal failure.
- Diagnosis: ANA’s-Generic, Anti-DS DNA, Anti-Smith, anti-histone, anti-phospholipid (causes false-positive syphilis test).
- Tx: Glucocorticoids
Goodpasture’s
- Autoimmune disease
- Etiology: Antibodies to 3 chain of type 4 collagen present in the basement membrane
- Pathogenesis: Type II hypersensitivity due to antibodies that cause destruction of the basement membrane in areas with small capillary beds such as the lung and the glomerulus.
- Clinical: Episode of progressive glomerulonephritis, pneumonitis (hemoptysis, focal consolidations, restrictive lung disease) with unknown trigger. Cause of death: Uremia.
- Path:
- Lung: Hemosiderin laden macrophages and type 2 pneumocyte hypertrophy, fibrous septate thickening.
- Kidney: Focal proliferative glomerulonephritis with crescentic morphology.
- Both: Linear deposition of IG along the basement membrane.
- Diagnosis: Percutaneous renal biopsy
- Tx: Plasmapheresis or immunosuppression.
Wegner’s Granulomatosis
- Systemic necrotizing granulomatous vasculitis of small and medium arteries and veins
- Etiology: Genetic
- Pathogenesis: Anti-neutrophil cytoplasmic antibodies (ANCAs) are responsible for inflammation, granuloma formation,and necrosis of vasculature causing end organ damage associated with the wide variety of symptoms seen.
- Clinical:
- Acute/Chronic
- Upper/lower respiratory
- Ulceration, septal perforation, saddle nose deformity, sinusitis, pulmonary infiltrates, nodules with cavitation, hemorrhage, obstructive or restrictive lung disease)
- Renal involvement
- Crescentic glomerulonephritis with renal insufficiency.
- Fever
- Weight loss
- Myalgias/arthralgias
- Cutaneous: purpura, ulcers, gangrene
- Neurologic: peripheral neuropathy, cranial neuropathy, infarction, hemorrhage, seizures
- GI: Abdominal pain, diarrhea, bleeding, ulcerations, infarction
- Cardiac: Pericarditis, arteritis, conduction defects, cardiomyopathy
- GU
- Diagnosis: Renal biopsy with crescentic GN, granuloma formation, and fibrinoid necrosis. Presence of C-ANCA. + Rheumatoid factor.
- Tx: Cyclophosphamide, corticosteroids.
Spirometry Interpretations
- FVC: Forced vital capacity
- FEV-1: Forced expiratory volume in one second
- FEF 25-75%: Forced expiratory flows between 25-75% of volume
- Obstructive
- Increased resistance within the lung causing decreased flows
- FVC: Normal
- FEV-1: Decreases
- FEV1/FVC: Decreases
- Restrictive
- Loss of effective lung volume
- FVC: Decreases
- FEV-1: Decreases
- FEV1/FVC: Normal to increased
Quantifying Renal Function
- GFR x Pinulin = V x Uinulin GFR = (V x Uinulin) / Pinulin
- Can also be done using creatinine, but this overestimates GFR because creatinine is secreted from the tubules as well as being filtered.
- Clearance: Volume of plasma cleared of a substance per unit time
- If clearance is > Cin the substance is filtered + secreted
- If clearance is < Cin the substance is filtered + reabsorbed
- Effective renal plasma flow: (Upah x V)/Ppah
- RPF: ERPF/.9
- Renal Blood Flow: ERPF / (1-HCT)
- FF: GFR/RPF (amount of plasma that flows through the kidney that is filtered by the glom)
- Fractional Excretion: FEx = (Ux x V) / (Px x GFR)
- Fractional Reabsorption: FRx = 1- FEx
Antibiotic Review- See Mike’s Presentation
- Identify categories of diseases that result in hemoptysis and specific disease processes in each category.
- Airway Disease
- Upper-obstruction, trauma, mucosal ulceration, bronchitis, infection, neoplasm
- Lower-obstruction, neoplasm, trauma, infection
- Pulmonary parenchymal disease: PF, ARDS, infection (tuberculosis, coccidiodes), autoimmune disease (lupus, Goodpasture’s, Wegener’s), iatrogenic, cocaine use
- Pulmonary vascular disease: PE, AVM (osler-weber-rendupresents w/telangiectasia), pulmonary hypertension
- Cryptogenic
- Explain the utility of urinalysis in the diagnosis of renal disease and the particular significance of red blood cell casts.
- Components of Urinalysis:
- Color/consistency
- Protein +/-
- pH
- Osmolality/specific gravity
- Glucose +/-
- Bacteria +/-
- Cells
- Casts
- The components of a urinalysis, as shown above, are many and varied. There are also a number of specific urine tests that can be ordered that examine for the presence/absence of specific molecules to help evaluate specific disease process (ie porphobilinogen in porphyria). Urinalysis is a helpful tool in evaluating the cause of renal/urinary disease because there are characteristic findings which are strongly suggestive of specific diagnoses.
- RBC casts indicate glomerulonephritis (glomerular inflammation), and can help differentiate renal disease that presents with hematuria from cystitis that presents with hematuria (which would show RBC’s without casts).
- Explain potential pathogenic mechanisms underlying disease processes that produce the syndrome of pulmonary alveolar hemorrhage and acute glomerulonephritis (red cell casts, and renal insufficiency).
- Post-streptococcal glomerulonephritis: Antibodies to the group b strep M antigen can be cross-reactive with the glomerular basement membrane and cause glomerulonephritis secondary to a streptococcal infection.
- Goodpasture’s Syndrome:Short-lived circulating of antibodies directed against the -chain of type 4 collagen (found in the basement membrane) attach to the GBM and the alveolar BM inciting inflammation and the classical presentation of glomerulonephritis and hemoptysis. Inciting stimulus is unknown.
- Lupus: Lupus is an autoimmune disorder in which circulating anti-nuclear antibody complexes deposit in tissues and incite an inflammatory response that causes tissue damage.
- Wegener’s: Wegener’s is an autoimmune disorder that is the result of antibodies to neutrophil granule proteins that cause release of inflammatory mediators that cause a systemic vascular inflammation. The production of anti-neutrophil cytoplasmic antibodies (ANCAs) is one of the hallmarks of WG.