Spaceflight urinary tract infection

Background

  • Over the years, several astronauts aboard the Space Shuttle, International Space Station (ISS), and other spacecraft have been diagnosed with UTIs, resulting in a range of outcomes.[1]
    • Fred Haise, the lunar module pilot of Apollo 13, developed a urinary tract infection during his mission that progressed to pyelonephritis, with lethargy, fevers, and flank pain persisting throughout the duration of the mission.[2]
    • In 1985, Russian cosmonaut Vladimir Vasyutin underwent a pre-mature de-orbit from the space station Salyut 7 due to a case of prostatitis.[3]
  • Urinary retention, a common issue during spaceflight, is a significant risk factor for developing UTIs. Astronaunts with urinary retention are 25 times more likely to have a UTI with a 17% infection rate per mission.[4]
    • Maintaining aseptic technique during catheterization for urinary retention management is an additional risk factor for developing UTIs during spaceflight, on top of the risk posed by urinary retention itself.[5]
  • Simulations suggest that UTIs in female astronauts predisposes them to a greater likelihood of medical evacuation compared to men during 6-month and 2.5-year missions.[6]

Genitourinary infection

(1) Human urinary system: (2) kidney; (3) renal pelvis; (4) ureter; (5) urinary bladder (6) urethra.
Additional structures: (7) adrenal gland; (8) renal artery and vein; (9) inferior vena cava; (10) abdominal aorta; (11) common iliac artery and vein; (12) liver; (13) large intestine; (14) pelvis.

"UTI" frequently refers specifically to acute cystitis, but may also be used as a general term for all urinary infections; use location-specific diagnosis.

Clinical Features

  • Uncomplicated UTI
    • Nonpregnant, premenopausal women without further risk factors for infection, treatment failure, or serious outcomes
  • Complicated UTI
    • Risk factors for infection, treatment failure, or serious outcomes including:
      • Male sex
      • Pregnancy
      • Postmenopause
      • Anatomical or functional abnormalities
      • Immunosuppression
      • Renal failure
      • Metabolic disorders (e.g., diabetes)
      • Infection associated with recent instrumentation or medical devices (e.g. Indwelling catheters)
  • Lower UTI symptoms
    • Dysuria
    • Hematuria
    • Increased urinary frequency
    • Suprapubic tenderness
    • Urinary urgency
  • Upper UTI symptoms (Pyelonephritis)
    • Lower UTI symptoms
    • Costovertebral angle tenderness
    • Fatigue/malaise
    • Fever
    • Nausea and vomiting

Differential Diagnosis

  • Infectious
    • Urethritis from sexually transmitted infections (e.g., Neisseria gonorrhoeae, Chlamydia trachomatis), Candida, or irritants
    • Tuberculous cystitis
  • Inflammatory
    • Drug-induced (e.g., cyclophosphamide, NSAIDs) or radiation-induced cystitis
    • Interstitial cystitis
    • Hemorrhagic cystitis
    • Pelvic inflammatory disease
    • Prostatitis
    • Vaginitis
  • Other
    • Asymptomatic bacteriuria
    • Bladder cancer
    • Foreign objects
    • Structural abnormalities of the urethra (e.g., diverticula, strictures)
    • Trauma
    • Urolithiasis

Space medicine

Evaluation

  • Assessment of pertinent genitourinary and constitutional symptoms is necessary to differentiate between lower and upper urinary tract infections, as well as between complicated and uncomplicated infections.
  • A comprehensive review of the astronaut's medical history, focusing on any previous experiences with urinary tract infections, as well as identifying risk factors and underlying conditions.
  • Pre-flight training and simulations may help anticipate susceptibility.

Workup

  • Tracking the onset, duration, and intensity of symptoms
  • Assessment of Vitals
  • Physical Exam
  • Urine Dipstick

Diagnosis

  • UTIs are primarily a clinical diagnosis that are supported by typical findings of pyruia (positive leukocyte esterase), bacteriruia (positive urinary nitrites), and occasionally hematuria on urine dipsticks available in pre-packaged ISS and Space Shuttle medical kits.[7]
  • ISS has more advanced diagnostic tools, enabling measurement of blood leukocytes if clinical suspicion of urosepsis. With guidance from the ground, ultrasound can also be used to image genitourinary organs to rule out complications such as concomitant renal calculi.[8]
  • Urine culture is indicated in select cases on earth to determine the causative pathogen and adapt antibiotic treatment; however, urine cultures are not routinely conducted aboard spacecraft due to limited laboratory and sterile handling conditions.[9]
    • E. Coli is thought to be the most common cause of UTIs in space flight, but this has yet to be verified. Broad spectrum coverage of Pseudomonas species is necessary as well, because this has been an offending organism recorded in previous spaceflight.[10]

Management

  • Empiric antibiotic treatment[11]
    • 1st-Line
      • Nitrofurantoin
        • Acute or prophylactic treatment of UTIs
        • NOT available in ISS and Space Shuttle medical kits
      • Sulfamethoxazole and Trimethoprim (Bactrim DS)
        • Available on IISS and Space Shuttle medical kits
    • 2nd-Line
      • Amoxicillin (Amoxil) or Ceftriaxone (Rocephin)
        • Adversely affects indigenous normal flora
        • Available in ISS and Space Shuttle medical kits
      • Levofloxacin (Levaquin)
        • Reserved for more complicated or refractory UTIs
        • Available in ISS and Space Shuttle medical kits
  • Oral analgesia can provide additional relief.
    • Acetaminophen (available in ISS and Space Shuttle medical kits)
    • Aspirin (available in ISS and Space Shuttle medical kits)
    • Ibuprofen (available in ISS and Space Shuttle medical kits)
  • Removal of indwelling catheters as the risk of developing a UTI increases each day one is left in the urinary system. [12]
  • Behavioral modifications, e.g. increased fluid intake, may be helpful.
  • Topical estrogen therapy may be considered in peri-menopausal and postmenopausal women.
  • De-orbit and intravenous treatment may be required if astronaut exhibits signs of shock or urosepsis (e.g. tachycardia, hypotension, tachypnea, flank pain, etc.).

Disposition

  • Spacecraft and space stations are equipped to diagnose and treat UTIs.
  • Among US astronauts diagnosed with UTIs on the Space Shuttle and ISS, all have been treated successfully with antibiotics and none required early mission termination.[13]
  • Pre-flight screening and risk mitigation are of importance to decrease the risk of in-flight urinary tract infections

See Also

References

  1. Jones J, Pietrzyk RA, Cristea O, Whitson PA. Chapter 18: Renal and Genitourinary Concerns. In: Barratt MR, Baker E, Pool SL, eds. Priciples of Clinical Medicine for Spaceflight. Springer Nature; 2020.
  2. Johnston RS, Dietlein LF, Berry CA, Parker JF Jr, West V, Jones WL. Biomedical Results of Apollo. NASA-SP-368. National Aeronautics and Space Administration; 1975.
  3. Jones JA, Jennings R, Pietryzk R, Ciftcioglu N, Stepaniak P. Genitourinary issues during spaceflight: a review. Int J Impot Res. 2005;17 Suppl 1:S64-S67. doi:10.1038/sj.ijir.3901431
  4. Law J, Cole R, Young MH, Mason S. NASA Astronaut Urinary Conditions Associated with Spaceflight. Presented at: Annual Scientific Meeting of the Aerospace Medical Association; April 24-28, 2016; Atlantic City, NJ.
  5. Law J, Cole R, Young MH, Mason S. NASA Astronaut Urinary Conditions Associated with Spaceflight. Presented at: Annual Scientific Meeting of the Aerospace Medical Association; April 24-28, 2016; Atlantic City, NJ.
  6. Reyes DP, Masterova KS, Walton M, Kerstman EL, Antonsen EL. Assessment of Sex-Dependent Medical Outcomes During Spaceflight. J Womens Health (Larchmt). 2022 Aug.
  7. Pahira JJ. Urinalysis: a comprehensive review [published correction appears in Am Fam Physician. 2006 Oct 1;74(7):1096]. Am Fam Physician. 2005;71(6):1153-1162.
  8. KAHLENBERG, Zachary Benjamin et al. Urologic Innovation in the Spaceflight Environment: Challenges, Opportunities, and Future Directions. Medical Research Archives, [S.l.], v. 9, n. 9, sep. 2021.
  9. KAHLENBERG, Zachary Benjamin et al. Urologic Innovation in the Spaceflight Environment: Challenges, Opportunities, and Future Directions. Medical Research Archives, [S.l.], v. 9, n. 9, sep. 2021.
  10. Barratt MR, Pool SL. Principles of Clinical Medicine for Spaceflight. Houston, TX: Springer; 2008.
  11. Barratt MR, Pool SL. Principles of Clinical Medicine for Spaceflight. Houston, TX: Springer; 2008.
  12. Pappas PG, Kauffman CA, Andes DR, et al. Clinical Practice Guideline for the Management of Candidiasis: 2016 Update by the Infectious Diseases Society of America. Clin Infect Dis. 2016;62(4):e1-e50. doi:10.1093/cid/civ933
  13. KAHLENBERG, Zachary Benjamin et al. Urologic Innovation in the Spaceflight Environment: Challenges, Opportunities, and Future Directions. Medical Research Archives, [S.l.], v. 9, n. 9, sep. 2021.