Young Syndrome

Definition

1. Chronic sinusitis
2. Bronchiectasis
3. Obstructive azoospermia (with normal spermatogenesis)

Etiology and Pathophysiology

• Mercury poisoning - The incidence of Young syndrome has declined dramatically since the 1970s, coinciding with the ban on mercurous chloride (calomel), which was used in teething powders and anthelmintics. This temporal relationship strongly supports mercury exposure as a key etiologic factor.
• Abnormal ciliary function or mucus quality - Ciliary beat frequency and ultrastructural anatomy are generally normal (unlike primary ciliary dyskinesia/Kartagener syndrome), but mucociliary clearance is prolonged nearly threefold compared to controls. In at least one case, ~13% of epididymal cilia showed microtubular disarrangement (malformation of radial spokes and dynein arms). Abnormally thick, viscous secretions are produced.

Comparison with Similar Conditions

Clinical Presentation

• Recurrent sinopulmonary infections beginning in childhood or early adulthood
• Chronic productive cough
• Bronchiectasis on imaging
• Male infertility (presenting complaint in many cases)
• Normal testicular size and normal serum FSH (indicating intact spermatogenesis)
• Palpable vas deferens and epididymides bilaterally (unlike CF/CBAVD)
• Mild respiratory symptoms compared to CF; no GI involvement

Diagnosis

1. Recurrent sinopulmonary infections (sinusitis, bronchiectasis)
2. Persistent azoospermia with normal spermatogenesis (confirmed by testicular biopsy or normal FSH/testicular size)
3. Obstruction at the epididymis on examination
4. Exclusion of CF (normal sweat chloride, no CFTR mutations)
5. Exclusion of immotile cilia syndrome / PCD (normal ciliary ultrastructure on EM, normal sperm motility in other contexts)

Classification

Management

• Antibiotics for acute bacterial sinopulmonary infections
• Inhaled bronchodilators (e.g., albuterol) and hypertonic saline to loosen airway secretions
• Airway clearance physiotherapy
• Surgical reconstruction (vasoepididymostomy) for fertility - however, success rates are lower than for other obstructive conditions
• Assisted reproduction - surgical sperm retrieval (e.g., MESA, TESE) combined with ICSI can achieve fatherhood

Key Points to Remember

• Triad: sinusitis + bronchiectasis + obstructive azoospermia
• Normal sweat test and pancreatic function (unlike CF)
• Normal ciliary ultrastructure (unlike Kartagener syndrome)
• Obstruction is at the epididymis, not the vas deferens
• Declining incidence since mercury-containing teething powders were banned
• Men with this triad should be tested for CFTR mutations before a definitive Young syndrome label is applied

Ciliary Dyskinesia Syndromes with Situs Inversus / Asplenia

The Underlying Mechanism

• The L-R signal is randomized → producing situs inversus (mirror image) in ~50% of cases
• The L-R signal is absent or chaotic → producing situs ambiguus / heterotaxy, which is when asplenia appears

The Syndromes

1. Kartagener Syndrome (Classic)

• Part of Primary Ciliary Dyskinesia (PCD)
• Triad: Situs inversus totalis + bronchiectasis + chronic sinusitis
• Spleen is present and normal (just on the wrong side, mirrored)
• ~50% of PCD patients develop situs inversus totalis (random chance from dysfunctional nodal cilia)
• Absent dynein arms on electron microscopy
• No asplenia

2. Heterotaxy Syndrome (Situs Ambiguus) - Right Isomerism = Asplenia Syndrome

• Also known as Ivemark syndrome (Ivemark sequence)
• Results from failure to establish the L-R axis (bilateral right-sidedness)
• Features:
  • Asplenia (or hypoplastic spleen) - because the spleen is a left-sided organ; bilateral right-sidedness means no spleen develops
  • Bilateral right-sided (trilobed) lungs and eparterial bronchi
  • Complex congenital heart defects (single ventricle, AV canal, anomalous pulmonary venous return, transposition)
  • Liver midline or right-sided
  • Intestinal malrotation
  • Dextrocardia (but NOT situs inversus totalis - incomplete/ambiguous)
• ~9-12% of PCD patients develop heterotaxy/situs ambiguus
• The spleen absence predisposes to fulminant infections by encapsulated bacteria (Streptococcus pneumoniae, Haemophilus, Neisseria)

3. Heterotaxy Syndrome - Left Isomerism = Polysplenia Syndrome

• Bilateral left-sidedness
• Polysplenia (multiple small spleens, may be functionally inadequate)
• Bilateral bilobed lungs
• IVC interruption with azygos continuation
• Complex heart defects (less severe than right isomerism)
• No asplenia

Summary Table

Key Takeaway

Ivemark syndrome (Right Isomerism / Asplenia Heterotaxy) - a form of PCD/heterotaxy where nodal cilia fail to generate directional flow, resulting in bilateral right-sidedness, absence of the spleen, complex heart defects, and ambiguous organ positioning.

Treatment of Kawasaki Disease

1. Acute Phase Treatment (All Patients)

A. IVIG (Intravenous Immunoglobulin) - FIRST-LINE

• Dose: 2 g/kg as a single infusion over 10-12 hours
• Timing: Must be given within the first 10 days of illness (ideally days 5-9)
• Reduces coronary artery dilation risk from ~20-25% down to <3%
• Reduces incidence of coronary artery aneurysms fivefold vs aspirin alone
• Can still be given after day 10 if ESR/CRP remain elevated with persistent fever
• Treatment with IVIG + aspirin reduces CAA prevalence from ~25% (aspirin alone) to ~5%

B. Aspirin - GIVEN ALONGSIDE IVIG

Note: Ibuprofen antagonizes the antiplatelet effect of aspirin and should be avoided. Use acetaminophen for fever instead.

2. High-Risk Patients - Adjunctive Therapy (2024 AHA Update)

• Age ≤ 6 months
• Baseline coronary artery z-score ≥ 2.5 on echocardiogram

Adjunctive Options:

3. IVIG Resistance (Refractory Kawasaki Disease)

1. Second dose of IVIG - 2 g/kg (first-line re-treatment)
2. Corticosteroids - IV methylprednisolone if second IVIG fails
3. Infliximab - 5-10 mg/kg IV (from KIDCARE trial data)
4. Non-glucocorticoid immunosuppressives (cyclosporine, anakinra) - for persistent fever despite above

4. Antithrombotic / Long-Term Therapy by Coronary Artery Status

5. Echocardiographic Follow-Up (All Patients)

• At diagnosis (baseline)
• At 2 weeks
• At 6-8 weeks
• At 12 months (optional if normal)
• More frequent if CAA or elevated z-scores present

6. Other Considerations

• Influenza vaccine: All children ≥6 months should receive inactivated (not live) influenza vaccine before discharge (and family members) - mandatory while on aspirin therapy to reduce Reye syndrome risk
• Live vaccines (MMR, varicella): Defer for 11 months after IVIG (may blunt immune response)
• Incomplete Kawasaki disease: Treat with IVIG promptly at diagnosis - do NOT delay until day 10