Hematuria + Breathlessness: Clinical Approach

Definition: Pulmonary-Renal Syndrome

"The term pulmonary-renal syndrome usually describes the presence of pulmonary hemorrhage in a patient with acute glomerulonephritis. Patients require urgent evaluation."

• Comprehensive Clinical Nephrology, 7th Ed.

Part 1 - Differential Diagnosis

A) Immune-Mediated (Pulmonary Hemorrhage + RPGN) - Most urgent

• Campbell Walsh Wein Urology, p. 664: "Hemoptysis and abnormal bleeding associated with microcytic anemia are characteristic of Goodpasture syndrome."
• Frameworks for Internal Medicine, p. 3784: A 44-year-old with chronic sinusitis presenting with dyspnea + hematuria + dysmorphic RBCs + RBC casts is GPA until proven otherwise.

B) Non-Immune (Fluid Overload / Infective / Other)

Part 2 - Immediate Evaluation

History

• Duration and character of hematuria (gross vs. microscopic; painless vs. painful; clots?)
• Nature of dyspnea: hemoptysis? (key - points to pulmonary hemorrhage), orthopnea, progressive?
• Upper respiratory symptoms / sinusitis (GPA)
• Rash, arthritis, mouth ulcers (SLE, IgA vasculitis)
• Drug history: penicillamine, hydralazine, propylthiouracil (drug-induced ANCA vasculitis)
• Recent sore throat or skin infection (post-streptococcal GN - children)
• Smoking history (Goodpasture's - triggers epitope exposure)

Physical Examination

• Vitals: BP (hypertension = nephritic), SpO2, temperature
• Lung exam: crackles, wheeze
• Skin: purpura, rash
• ENT: nasal septal perforation, saddle-nose (GPA)
• Edema, JVP

Urgent Investigations

• Dipstick + microscopy - dysmorphic RBCs and RBC casts = glomerulonephritis until proven otherwise
• 24h protein or urine PCR

• FBC (anemia from pulmonary hemorrhage/chronic inflammation)
• U&E, creatinine (AKI), LFTs
• CRP, ESR
• Serology panel (run urgently in parallel):
  • Anti-GBM antibodies
  • ANCA (c-ANCA/PR3, p-ANCA/MPO)
  • ANA, anti-dsDNA
  • C3, C4, CH50
  • Anti-streptolysin O (ASOT), cryoglobulins, hepatitis B/C serology
  • Blood cultures if infection suspected

• CXR: bilateral alveolar infiltrates (pulmonary hemorrhage resembles pulmonary edema but without cardiomegaly/effusions)
• CT chest if CXR equivocal
• Renal ultrasound

• Urgent renal biopsy in suspected immune-mediated causes
• In Goodpasture's: shows focal/segmental necrosis + crescent formation + linear IgG immunofluorescence
• Do NOT delay biopsy - provides both diagnosis AND prognosis

Part 3 - Management

Emergency Stabilization

• Oxygen/ventilatory support for hypoxemia
• IV access, fluid management (balance resuscitation vs. volume overload)
• If pulmonary hemorrhage: avoid excess fluids
• Urgent nephrology + pulmonology consult

Disease-Specific Treatment

• Plasmapheresis (8-10 sessions) - removes circulating anti-GBM antibodies; especially effective for lung hemorrhage
• Oral prednisolone + cyclophosphamide for immunosuppression
• Maintain until anti-GBM titers are negative
• Prognosis poor if: creatinine >5-6 mg/dL, oliguria, >50% crescents on biopsy, need for dialysis
• Kidney transplant only after 6 months AND undetectable serum antibodies
• Harrison's 22E, p. 2462

• Induction: IV methylprednisolone pulse x 3 days, then oral prednisolone + cyclophosphamide OR rituximab
• Maintenance: azathioprine or rituximab (lower relapse rate with rituximab in GPA)
• GPA has higher relapse rate than MPA - requires diligent follow-up
• Brenner & Rector's Kidney, p. 1284

• Steroids + mycophenolate mofetil (Class III/IV) or hydroxychloroquine
• Belimumab or voclosporin as add-on for refractory disease

• Treat underlying AKI/cardiac failure
• Diuretics; dialysis if severe AKI
• Antibiotics if infective cause (Legionella, leptospirosis)

Key Red Flags - Escalate Urgently

• Hemoptysis + hematuria + RBC casts = pulmonary-renal syndrome - start workup and empiric steroids before biopsy results return if rapidly deteriorating
• Rapidly rising creatinine = RPGN - renal biopsy within hours, not days
• Falling SpO2 = pulmonary hemorrhage may be massive; intubation may be needed
• Oliguria/anuria = dialysis urgently

Summary Algorithm

Hematuria + Breathlessness
         |
   RBC casts on urine microscopy?
    YES → Glomerulonephritis + Pulmonary involvement
         → Urgent anti-GBM, ANCA, ANA, C3/C4
         → Renal biopsy ASAP
         → Pulmonology + Nephrology
    NO  → Consider: AKI + volume overload, RCC + mets,
          PE + renal vein thrombosis, Infection
         → Echo, CT chest/abdomen, Doppler USS

• Comprehensive Clinical Nephrology, 7th Ed. (Box 25.3, 25.4)
• Harrison's Principles of Internal Medicine 22E (Anti-GBM Disease, p. 2462)
• Frameworks for Internal Medicine (Pulmonary-Renal Syndrome framework)
• Brenner & Rector's Kidney (ANCA vasculitis treatment)
• Campbell Walsh Wein Urology (Glomerular hematuria)

Snakebite with No Symptoms, No Swelling, No Pain

This is a "Dry Bite"

"A venomous animal may bite or sting without injecting enough venom to cause effects (a 'dry bite'), so signs of envenomation will not always develop. In the United States, viperid bites have about a 20% dry bite rate, whereas elapid bites have about a 50% dry bite rate."

• Goldman-Cecil Medicine

"Up to 25% of crotaline snakebites are dry bites: venom effects do not initially develop."

• Tintinalli's Emergency Medicine

Why Symptoms May Still Develop Later

• Local swelling in pit viper bites may not appear for several hours after the bite
• Elapid (cobra, coral snake, mamba) bites can have a particularly dangerous "silent interval" - local signs are minimal or absent, but neurotoxic paralysis can appear hours later, including respiratory failure
• An "initially minimal bite may evolve into a more serious bite and require large amounts of antivenom" - Tintinalli's EM

Immediate Management Protocol

Step 1 - Emergency Department Assessment

• Snake species if known (color, shape, habitat)
• Time of bite
• Any first aid already applied
• Tetanus immunization status

• Confirm fang mark(s) present
• Baseline vitals: BP, HR, RR, SpO2
• Measure circumference of bitten limb and mark the advancing edge of any swelling with a pen + time (serial skin marking - see Fig. 44.5)
• Neurological exam: ptosis, diplopia, dysarthria, limb weakness (early neurotoxicity)
• Check for bleeding from gums, IV sites (coagulopathy)

Step 2 - Baseline Investigations (Mandatory Even if Asymptomatic)

"Absence of any manifestations [local injury, hematologic abnormality, systemic effects] for a period of 8 to 12 hours following the bite indicates a dry bite."

• Tintinalli's Emergency Medicine

Observation Period - How Long?

"In locales such as Australia where there is a preponderance of Elapid envenomations, the observation time should be extended because local skin changes may be minimal."

• Sabiston Textbook of Surgery

"All children with envenomation and coral snake bites should be admitted for observation."

• Rosen's Emergency Medicine

What to Monitor During Observation

1. Local effects - swelling progression (re-mark skin), pain, ecchymosis, blistering
2. Systemic effects - vital signs, nausea/vomiting, metallic taste, oral paresthesias, ptosis
3. Neurological - limb power, cranial nerve function (elapids)
4. Repeat labs at 6 hours - coagulation, platelet count

What NOT to Do (Common Harmful Practices)

Indications to Give Antivenom (even if initially asymptomatic)

• Progressive local swelling beyond bite site
• Ecchymosis, blistering, hemorrhagic changes
• Thrombocytopenia, rising PT/APTT, falling fibrinogen
• Any systemic symptoms: hypotension, tachycardia, neurological signs
• Coagulopathy (even if no clinical bleeding)

"All snakebite patients who develop progressive signs and symptoms should be treated promptly with antivenom. Progression is defined as worsening of local injury, abnormal laboratory results, or systemic manifestations."

• Tintinalli's Emergency Medicine

Tetanus

• Administer tetanus toxoid to all snakebite patients regardless of symptoms
• Sabiston Textbook of Surgery

Discharge Criteria (Only if ALL of these are met)

• No symptoms after full observation period (8-12h pit vipers; 24h elapids)
• Normal and stable serial labs (coagulation, platelets)
• No local progression of any swelling
• Reliable patient with transport and ability to return
• Discharge instructions: Return immediately if swelling, bruising, bleeding, weakness, difficulty swallowing/breathing, or any new symptoms develop within 24-48 hours

Summary

Snakebite → No symptoms at presentation
                    ↓
         DO NOT DISCHARGE immediately
                    ↓
  Establish IV access + baseline labs + serial limb marking
                    ↓
     Observe: 8-12 hrs (pit viper) | 24 hrs (elapid/unknown)
                    ↓
   Still asymptomatic + normal labs → Discharge with instructions
   Any progression → Antivenom + Admit

• Tintinalli's Emergency Medicine, Ch. 212 (Snakebite)
• Sabiston Textbook of Surgery, Ch. 44 (Snakebite Management)
• Goldman-Cecil Medicine (Envenomation Pathobiology)
• P.C. Dikshit Textbook of Forensic Medicine and Toxicology (First Aid)
• Rosen's Emergency Medicine (Dry bite / Observation)