Rheumatic Fever

Pathophysiology:

• Inflammatory disease occurring 2–4 weeks after an untreated group A strep infection (strep throat or scarlet fever), primarily affecting children aged 5–15
• Connective tissue of heart, joints, CNS, subcutaneous tissues are targeted by immune reaction

Clinical Features:

• Polyarthritis, pericarditis, Sydenham’s chorea, erythema marginatum, nodules

Workup:

• CMC, CMP, ESR, CRP

• ASO (Antistreptolysin O) titer Elevated 1week to 1 month after GAS infection
• Anti-DNase B titer is elevated longer than ASO and may be useful for patient presenting later than 2-4 months or with a negative ASO
• ECG – Looking for prolonged PR or other AV block
• CXR
• Echocardiogram

Management:

• Eliminate underlying streptococcus bacteria with antibiotics (penicillin), reducing inflammation, pain, and fever with aspirin or other NSAIDs. Consider corticosteroids for heart inflammation.
• Long-term, secondary prevention with regular antibiotic injections (Penicillin G IM x1 month) to prevent recurrence and heart damage

Tumor Lysis Syndrome

Overview:

• Occurs when large numbers of cancer cells die and release their contents into the circulatory system
• Usually with onset of new chemotherapy or high tumor burden.
• -K, Phosphate, calcium, nucleic acids -> urine acid, proteins
• Can lead to AKI and renal failure
• Usually within 72 hours, can have later presentation up to 10 days (i.e.. Immune checkpoint inhibitors)
• Laboratory or clinical diagnosis

Risk factors:

• Cancer type (NHL, Lymphoma, AML, and ALL most common).
• Solid tumors with high tumor burden
• Age, kidney function, dehydration, renal and CNS involvement, presence of mediastinal mass, LDH >2x upper limit of normal indicates rapid cell turnover

Clinical Presentation:

• Nonspecific, commonly involved the renal, neurological, and cardiac systems
• Trousseau-muscle spasm with inflation of BP cuff = hypocalcemia

Workup:

• CBC, CMP, Phosphorus, Calcium, Uric Acid, LDH, EKG, UA
• Cairo-Bishop Diagnostic Criteria

Management:

• Treat electrolyte derangements, IVF (2-3x maintenance fluid dose), manage uric acid (rasburicase or allopurinol)
• Consult Heme Onc, Renal
• Likely admit

ITP (Immune Thrombocytopenic Purpura) Case

Overview:

• Immune mediated destruction of platelets
• Primary (idiopathic) vs Secondary (part of larger pathology or medications)
• Presentation: Petechia, purpura, epistaxis, gingival bleeding, mouth lesions, acute bleeds
• Thrombocytopenia plt < 100 with no change in other cell lines
• Need to differentiate between others (ITP, HIT, HUS, TTP, DIC)

Treatment:

• Minor OR Platelet < 30: Dexamethasone 40 mg IV
• Severe: Dexamethasone 40 mg IV, IVIG 1g/kg, Plt transfusion (goal 50-100), splenectomy?
• Treatment same in pregnant patients and pediatrics.

Diving Medicine

Key History to Obtain:

• Dive depth
• Dive duration
• Number of dives
• Ascent rate
• Safety stops performed
• Time since surfacing
• Air source
• Prior dive illness
• Look at diving watch to obtain this data quickly

1. Decompression Sickness (DCS)

Related to nitrogen bubble formation during ascent.

Mechanism:

• Increased pressure underwater dissolves nitrogen into tissues.
• Rapid ascent → nitrogen comes out of solution → bubbles form in blood/tissues.

Types:

Type I (Mild)

• Musculoskeletal pain (“the bends”)
• Joint pain (shoulder, elbow, knee most common)
• Skin findings
  • Pruritus
  • Mottled rash (cutis marmorata)

Type II (Severe): Involves neurologic, pulmonary, or vestibular systems

• Weakness
• Paresthesia
• Paralysis
• Ataxia
• Bladder dysfunction
• Confusion
• Vertigo
• Hearing loss

Pulmonary form (the chokes):

• Chest pain
• Cough
• Dyspnea

Diagnosis: Recent dive (usually within 6–24 hours), Compatible symptoms

Treatment:

1. 100% Oxygen
2. IV fluids
3. Supine positioning
4. Immediate hyperbaric consultation
5. Recompression therapy

Hyperbaric therapy dramatically improves outcomes.

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2. Arterial Gas Embolism (AGE)

Most dangerous diving emergency.

Mechanism

• Rapid ascent → lung overexpansion → alveolar rupture
• Air enters pulmonary veins → systemic embolization

Presentation (often within minutes of surfacing)

Neurologic symptoms:

• Stroke-like deficits
• Seizures
• Altered mental status
• Paralysis
• Vision changes

Other symptoms:

• Chest pain
• Dyspnea
• Cardiac arrest

Treatment:

Same as severe DCS:

1. 100% Oxygen
2. Hyperbaric recompression (urgent)
3. IV fluids

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3. Barotrauma

Occurs when air spaces cannot equalize pressure.

Ear Barotrauma (Most Common)

-Severe ear pain with descent. If ears are not equalized, pressure builds and eustachian tube collapses. Clear ears on water entry and often during dive.

Symptoms:

• Ear pain
• Hearing loss
• Vertigo
• TM rupture

Exam:

• Hemotympanum
• TM perforation

Treatment:

• Analgesia
• ENT follow-up
• Avoid further diving
• Give antibiotics only for perforated TM

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Sinus Barotrauma

Symptoms:

• Facial pain
• Epistaxis
• Sinus pressure

Treatment:

• Decongestants
• Analgesia

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Pulmonary Barotrauma

Causes:

• Pneumothorax
• Pneumomediastinum
• Arterial gas embolism

Symptoms:

• Chest pain
• Dyspnea
• Subcutaneous emphysema

Treatment:

• Manage pneumothorax
• Oxygen
• Hyperbaric if embolism suspected

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4. Nitrogen Narcosis

Occurs at depth >30 meters (~100 ft).

Symptoms:

• Euphoria
• Poor judgment
• Confusion
• Impaired coordination

Treatment:

• Ascend to shallower depth

Symptoms resolve quickly, it is safe to continue diving after resolution of symptoms.

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Immediate ED Management

1. High-flow oxygen
2. IV fluids
3. Neurologic exam
4. Call hyperbaric center
5. Transport if needed

In the U.S., consultation is often through:

• Divers Alert Network, they assist with hyperbaric referral and organizing transfer

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Board Pearls

• Any neurologic symptom after diving = assume AGE or DCS → hyperbaric therapy
• Symptoms within minutes of surfacing → think AGE
• Symptoms hours later → think DCS
• Joint pain after diving = DCS Type I
• Stroke-like symptoms after diving = AGE until proven otherwise

Immunosuppression and Transplant

Common ED patients:

• Solid organ transplant
• Bone marrow transplant
• Chemotherapy
• Chronic steroids
  (>20 mg prednisone daily for >2 weeks)
• Advanced HIV
• Biologic therapy

Common immunosuppressive drugs:

• Typical regimen includes: calcineurin inhibitor + antimetabolite + steroid
• Calcineurin inhibitor (Cyclosporine, Tacrolimus)
• Steroids
• +/- Antimetabolite (Azathioprine, Mycophenolate mofetil)

Solid Organ Transplant Rejection:

• Hyperacute (Minutes–hours)
• Acute Rejection (Weeks–months)
• Chronic Rejection (Months–years)

Organ-Specific Rejection Clues:

Kidney Transplant:

• Rising creatinine
• Decreased urine
• Hypertension

Liver Transplant:

• Fever
• RUQ pain
• Elevated LFTs
• Jaundice

Heart Transplant:

• Dyspnea
• Heart failure symptoms
• Arrhythmias
• Because transplanted hearts are denervated, they may NOT present with typical chest pain.

Neutropenic Fever:

• ANC <500 OR <1000 with predicted nadir of <500 in 48h AND
• Fever ≥ 38.3˚C (100.9˚F) once OR sustained temperature ≥38 (100.4) for >1hr