My patient with sepsis and bacteremia has an extremely high serum Creatine kinase (CK) level. Can his infection be causing rhabdomyolysis?

 Absolutely! Although trauma, toxins, exertion, and medications are often listed as common causes of rhabdomyolysis, infectious etiologies should not be overlooked as they may account for 5% to 30% or more of rhabdomyolysis cases (1,2).

 

Rhabdomyolysis tends to be associated with a variety of infections, often severe, involving the respiratory tract, as well as urinary tract, heart and meninges, and may be caused by a long list of pathogens (1).  Among bacterial causes, Legionella sp. (“classic” pathogen associated with rhabdomyolysis), Streptococcus sp. (including S. pneumoniae), Salmonella sp, Staphylococcus aureus, Francisella tularensis have been cited frequently (3).  Some series have reported a preponderance of aerobic gram-negatives such as Klebsiella sp., Pseudomonas sp. and E. coli  (1,2).   Among viral etiologies, influenza virus, human immunodeficiency virus, and coxsackievirus are commonly cited (2,3).  Fungal and protozoal infections (eg, malaria) may also be associated with rhabdomyolysis (5).

 

So how might sepsis cause rhabdomyolysis? Several potential mechanisms have been implicated, including tissue hypoxemia due to sepsis, direct muscle invasion by pathogens (eg, S. aureus, streptococci, Salmonella sp.), toxin generation (eg, Legionella), cytokine-mediated muscle cell toxicity (eg, aerobic gram-negatives) as well as muscle ischemia due to shock (1,5).

 

Bonus Pearl: Did you know that among patients with HIV infection, infections are the most common cause (39%) of rhabdomyolysis (6)? 

 

Liked this post? Download the app on your smart phone and sign up under MENU to catch future pearls right into your inbox!

References

 

1. Kumar AA, Bhaskar E, Shantha GPS, et al. Rhabdomyolysis in community acquired bacterial sepsis—A retrospective cohort study. PLoS ONE 2009;e7182. Doi:10.1371/journa.pone.0007182. https://www.ncbi.nlm.nih.gov/pubmed/19787056.

2. Blanco JR, Zabaza M, Sacedo J, et al. Rhabdomyolysis of infectious and noninfectious causes. South Med J 2002;95:542-44. https://www.ncbi.nlm.nih.gov/pubmed/12005014

3. Singh U, Scheld WM. Infectious etiologies of rhabdomyolysis:three case reports and review. Clin Infect Dis 1996;22:642-9. https://www.ncbi.nlm.nih.gov/pubmed/8729203

4. Shih CC, Hii HP, Tsao CM, et al. Therapeutic effects of procainamide on endotoxin-induced rhabdomyolysis in rats. PLOS ONE 2016. Doi:10.1371/journal.pone.0150319. https://www.ncbi.nlm.nih.gov/pubmed/26918767

5. Khan FY. Rhabdomyolysis: a review of the literature. NJM 2009;67:272-83. http://www.njmonline.nl/getpdf.php?id=842

6. Koubar SH, Estrella MM, Warrier R, et al. Rhabdomyolysis in an HIV cohort: epidemiology, causes and outcomes. BMC Nephrology 2017;18:242. DOI 10.1186/s12882-017-0656-9. https://bmcnephrol.biomedcentral.com/track/pdf/10.1186/s12882-017-0656-9

My patient with sepsis and bacteremia has an extremely high serum Creatine kinase (CK) level. Can his infection be causing rhabdomyolysis?

My patient with cocaine and alcohol addiction is admitted with repeated convulsions during which he seems totally conscious. What could I be missing?

Consider strychnine poisoning as a cause of recurrent generalized tonic clonic seizures and muscle spasm with clear sensorium either during or following the episode. 1-4 In contrast to the cortical source of most seizures, convulsions due to strychnine poisoning are due to the blocking of the action of spinal and brain-stem inhibitory neurons resulting in overwhelming muscle rigidity, not unlike that seen in tetanus.

Although strychnine was found in various tonics and cathartic agents and was a common cause of accidental death in children under 5 years of age in early 20th century, it is still used in various rodenticides and pesticides.3  Today, it may be used intentionally in suicide attempts as well as an adulterant in street drugs, such as amphetamines, heroin and especially cocaine. 1,3,5

The initial symptoms of strychnine poisoning include nervousness, a hyperalert state, and confusion. These symptoms may be followed by severe muscle rigidity throughout the body often in response to minimal stimuli, such as physical contact, bright lights, noise and medical procedures.3, 6,7  Interestingly, strychnine also has an excitatory action on the medulla and enhances the sensation of touch, smell, hearing and sight.6  The cause of death is usually respiratory arrest due to prolonged muscle spasms, often complicated by rhabdomyolysis and associated renal failure.1

So among the numerous causes of seizures, think of strychnine as another potential cause when there is no concurrent loss of consciousness or the expected postictal state.

Bonus Pearl: Did you know that strychnine may be present in street drugs with a variety of names such as “back breakers”, “homicide”, “red rock opium”, “red stuff” and “spike”? 7

 

Liked this post? Download the app on your smart phone and sign up under MENU to catch future pearls right into your inbox, all for free!

 

References

  1. Wood DM, Webser E, Martinez D, et al. Case report: survival after deliberate strychnine self-poisoning, with toxicokinetic data. Critical Care 2002;6:456-9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC130147/
  2. Santhosh GJ, Joseph W, Thomas M. Strychnine poisoning. J Assoc Physicians India 2003;51:736. https://www.ncbi.nlm.nih.gov/pubmed/14621058
  3. Libenson MH, Young JM. Case records of Massachusetts General Hospital. A 16 years boy with an altered mental status and muscle rigidity. N Engl J Med 2001;344:1232-9. https://www.nejm.org/doi/full/10.1056/NEJM200104193441608
  4. Smith BA. Strychnine poisoning. J Emerg Med 1990;8: 321-25. https://www.ncbi.nlm.nih.gov/pubmed/2197324
  5. O’Callaghan WG, Ward M, Lavelle P, et al. Unusual strychnine poisoning and its treatment: report of eight cases. B Med J 1982;285:478. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1499293/
  6. Burn DJ, Tomson CRV, Seviour J, et al. Strychnine poisoning as an unusual cause of convulsions. Postgrad Med J 1989;65:563-64. https://www.ncbi.nlm.nih.gov/pubmed/2602253
  7. Radosavljevic J, Jeffries WS, Peter JV. Intentional strychnine use and overdose—an entity of the past? Crit Care Resusc 2006;8: 260-61. https://www.ncbi.nlm.nih.gov/pubmed/16930120

 

My patient with cocaine and alcohol addiction is admitted with repeated convulsions during which he seems totally conscious. What could I be missing?

200 pearls and counting! Take the Pearls4Peers quiz #2!

Multiple choice (choose 1 answer)
1. Which of the following classes of antibiotics is associated with peripheral neuropathy?
a. Penicillins
b. Cephalosporins
c. Macrolides
d. Quinolones

 

 

2. The best time to test for inherited thrombophilia in a patient with acute deep venous thrombosis is…
a. At least 1 week after stopping anticoagulants and a minimum of 3 months of anticoagulation
b. Just before initiating anticoagulants
c. Once anticoagulation takes full effect
d. Any time, if suspected

 

 

3. All the following is true regarding brain MRI abnormalities following a seizure, except…
a. They are observed following status epilepticus only
b. They are often unilateral
c. They may occasionally be associated with leptomeningeal contrast enhancement
d. Abnormalities may persist for weeks or months

 

 

4. Which of the following is included in the quick SOFA criteria for sepsis?
a. Heart rate
b. Serum lactate
c. Temperature
d. Confusion

 

 

5. All of the following regarding iron replacement and infection is true, except…
a. Many common pathogens such as E.coli and Staphylococcus sp. depend on iron for their growth
b. Association of IV iron replacement and increased risk of infection has not been consistently demonstrated
c. A single randomized-controlled trial of IV iron in patients with active infection failed to show increased infectious complications or mortality with replacement
d. All of the above is true

 

True or false

1. Constipation may precede typical manifestations of Parkinson’s disease by 10 years or more
2. Urine Legionella antigen testing is >90% sensitive in legionnaire’s disease
3. Spontaneous coronary artery dissection should be particularly suspected in males over 50 years of age presenting with acute chest pain
4. Urine dipstick for detection of blood is >90% sensitive in identifying patients with rhabdomyolysis and CK >10,000 U/L
5. Diabetes is an independent risk factor for venous thrombophlebitis

 

 

 

Answer key
Multiple choice questions:1=d; 2=a;3=a;4=d;5=c
True or false questions:1=True; 2,3,4,5=False

 

200 pearls and counting! Take the Pearls4Peers quiz #2!

What is the utility of urine dipstick for blood in diagnosing rhabdomyolysis?

Although the dipstick method of detecting blood in the urine is convenient, it cannot differentiate between hemoglobin, myoglobin, or red blood cells. 1

Several reviews suggest that urine myoglobin is unstable with subpar performance in rhabdomyolysis1, often defined as creatine kinase (CK) elevation 5 times the upper limit of normal in the proper context (eg, crush injury, hypoxic/ischemic or drug injury). A sensitivity of 71% and a specificity of 54% for urine hemoglobin by dipstick, and a sensitivity of 25% and specificity of 75%  for urine myoglobin  has been reported in patients with serum CK >10,000 U/L. 3  

So while a positive dipstick for blood with few or no RBCs in the urine may make us think about rhabdomyolysis, its absence should not be used to exclude it in a susceptible host.

Bonus Pearl: Did you know that consumption of quail has been associated with rhabdomyolysis, possibly due to their feeding on poisonous plants such as hemlock?

Liked this post? Download the app on your smart phone and sign up under MENU to catch future pearls right into your inbox, all for free!

 

References

  1. Rodriguez-Capote Karina, Balion CM, Hill SA, et al. Utility of urine myoglobin for the prediction of acute renal failure in patients with suspected rhabdomyolysis: A systematic review. Clin Chem 2009;55:2190-97. https://www.ncbi.nlm.nih.gov/pubmed/19797717
  2. Nance JR, Mammen AL. Diagnostic evaluation of rhabdomyolysis. Muscle Nerve 2015;51:793-810. https://www.ncbi.nlm.nih.gov/pubmed/25678154
  3. Grover DS, Atta MG, Eustace JA, et al. Lack of clinical utility of urine myoglobin detection by microconcentrator ultrafiltration in the diagnosis of rhabdomyolysis. Nephrol Dial Transplant 2004;19:2634-38. https://www.ncbi.nlm.nih.gov/pubmed/15280520
What is the utility of urine dipstick for blood in diagnosing rhabdomyolysis?

Is there a connection between cirrhosis and elevated CK or rhabdomyolysis?

Besides the usual causes of rhabdomyolysis such as trauma, drugs, alcohol, sepsis, etc…, cirrhotic patients may also have what some have called “hepatic myopathy”.  

One study involving 99 patients with cirrhosis and myopathy (all with elevated serum myoglobin) found “infections” as the most common cause (47%),  followed by “idiopathic” (27%) sources as well as ETOH, herbal medicine, and trauma-related causes (<10% each) (1). 

Whether this is truly an entity  or just a non-causal association is unclear to me. The question now is whether we should lower our threshold in ordering CK in these patients.

Reference

1. Lee O-J, Yoon J-H, Lee E-J, et al. Acute myopathy associated with liver cirrhosis. World J Gastroenterol 2006;12:2254-2258.  https://www.ncbi.nlm.nih.gov/pubmed/16610032 .

If you liked this post, sign up under MENU and get future pearls straight into your mailbox!

Is there a connection between cirrhosis and elevated CK or rhabdomyolysis?