Treatment Considerations for Brucellosis Patients on Hydroxychloroquine (HCQ)
When treating brucellosis in a patient who has been started on hydroxychloroquine, the recommended approach is to use doxycycline plus streptomycin as the first-line regimen, while carefully monitoring for potential drug interactions and retinal toxicity from HCQ. 1
First-Line Treatment Options for Brucellosis
- Doxycycline (100 mg twice daily orally for 6 weeks) plus streptomycin (15 mg/kg daily intramuscularly for 2-3 weeks) is the most effective regimen for brucellosis and should be considered the first choice, even in patients on HCQ 1
- Doxycycline plus gentamicin (5 mg/kg daily parenterally in 1 dose for 7 days) is an acceptable alternative first-line regimen with similar efficacy 1, 2
- Doxycycline plus rifampicin (600-900 mg daily for 6 weeks) has higher relapse rates compared to doxycycline-streptomycin but may be considered if aminoglycosides are contraindicated 1, 3
HCQ Monitoring Requirements
- Baseline ophthalmologic examination is recommended within the first year of starting HCQ to rule out preexisting maculopathy 1, 4
- For patients on acceptable doses without major risk factors, annual screening can be deferred until after 5 years of HCQ use 1, 4
- Annual screening should include automated visual fields and spectral-domain optical coherence tomography (SD-OCT) 1
- HCQ dosing should not exceed 5.0 mg/kg of actual body weight to minimize risk of toxicity 1
Potential Drug Interactions and Monitoring
- Monitor for hepatotoxicity: HCQ can cause elevated liver enzymes, and some brucellosis treatments (particularly rifampicin) may also affect liver function 5
- Check baseline and periodic complete blood count (CBC) and liver function tests (LFTs) for patients on combined therapy 4, 5
- Monitor for neuropsychiatric symptoms, as HCQ can cause neuropsychiatric reactions including suicidality 5
- Watch for hypoglycemia, which can be severe with HCQ, especially if the patient is on other medications that affect blood glucose 5
Special Considerations
- For patients with G6PD deficiency, monitor for hemolytic anemia as HCQ can exacerbate this condition 5
- In patients with renal impairment, dose adjustments may be needed for both HCQ and brucellosis treatments, particularly aminoglycosides 5
- For complicated brucellosis (spondylitis, neurobrucellosis), longer treatment duration may be required while continuing to monitor for HCQ toxicity 1
- In pregnant patients with brucellosis, rifampicin monotherapy may be safer than combination therapy, though this must be balanced against higher relapse rates 1
Alternative Regimens When HCQ Interactions Are Concerning
- Doxycycline plus cotrimoxazole (TMP-SMX 800+160 mg twice daily for 6 weeks) shows similar efficacy to doxycycline-rifampicin and may have fewer drug interactions with HCQ 1, 6
- Quinolone-containing regimens (ofloxacin 400 mg twice daily or ciprofloxacin 500 mg twice daily for 6 weeks) combined with rifampicin may be considered but have higher relapse rates 1, 7
Common Pitfalls and Caveats
- Avoid high-dose HCQ (>5.0 mg/kg actual body weight) as it significantly increases risk of retinal toxicity 1
- Do not stop HCQ casually for borderline findings on ophthalmologic screening, as it is a valuable medication 1
- Monotherapy for brucellosis has higher relapse rates (13% vs. 4.8%) compared to combination therapy and should be avoided 6
- Short-term treatment regimens (<4 weeks) for brucellosis have significantly higher relapse rates (22% vs. 4.8%) and should not be used 6
- Retinopathy from HCQ is not reversible, emphasizing the importance of proper dosing and regular screening 4
By following these guidelines, clinicians can effectively manage brucellosis while minimizing the risks associated with concurrent HCQ therapy.