UMEM Educational Pearls - By Andrea Tenner

Category: International EM

Title: XDR Tuberculosis

Keywords: XDR, tuberculosis, international, Eastern Europe, Russia (PubMed Search)

Posted: 8/14/2013 by Andrea Tenner, MD
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General Information:

XDR TB is “extensively drug resistant tuberculosis”—resistant to isoniazid, rifampin, any fluoroquinolone, and at least one of the 3 injectable 2nd line drugs

Clinical Presentation:

- Identical to regular TB (weight loss, fevers, night sweats, cough, hemoptysis)

- Suspect in patients who are failing usual treatment

-Exposure in Eastern Europe or Russia (highest prevalence, although 84 countries have had documented XDR, including the US.)

Diagnosis:

- Plating on agar or liquid media for drug susceptibility testing

Treatment:

- Should be guided by susceptibility testing

- Isolate the patient!

Bottom Line:

XDR TB is increasing in prevalence, have a high index of suspicion in patients with persistent symptoms who are receiving treatment and isolate if any concerns.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Category: International EM

Title: Diarrheal Disease Outbreak in the US

Keywords: cyclospora, outbreak, international, tropical, infectious disease (PubMed Search)

Posted: 7/31/2013 by Andrea Tenner, MD
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General Information:

As of July 30th, 2013, there have been 378 cases of Cyclospora  infection from multiple states in the US.  Cyclospora is most common in tropical and sub-tropical regions, and is spread via fecal-oral route.  While the cause of the most recent outbreak is unknown, outbreaks in the US are generally foodborne.

Clinical Presentation:

- Symptoms usually begin 7 days after exposure

- Watery diarrhea, cramping, bloating, nausea, fatigue, increased gas, vomiting, low grade temperature

- Can persist several weeks to > 1 month

Diagnosis:

- Concentrated Stool Ova and Parasites— viewed under modified acid fast or fluorescence microscopy (labs can submit photos to the CDC for “telediagnosis”)

Treatment:

- TMP-SMX DS one tab po bid x7-10 days

- No effective alternate for failed treatment or sulfa allergy

- Most will recover without treatment but S/S can persist for weeks to months

Bottom Line:

Consider Cyclospora as a cause of prolonged diarrheal illness, treat with TMP-SMX.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Category: International EM

Title: Hepatitis C Recommendations

Keywords: Hepatits C, Infectious Disease, International, Liver (PubMed Search)

Posted: 7/3/2013 by Andrea Tenner, MD (Updated: 4/18/2024)
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Background:

Infection with the Hepatitis C  virus can result in mild to severe liver disease.  Morbidity and mortality from Hep C is increasing the US--many of the 2.7-3.9 million persons with Hep C are not aware of their infection.

Pertinent Information:

- Hepatitis C is now curable for many patients

- Current treatment recommendations are a combination of medications (pegylated interferon plus ribavirin plus a protease inhibitor). 

- Research in this field is very active--treatment is likely to change in the next 3-5 years.

- Risk reduction strategies to protect the liver (i.e. eliminating alcohol and Hep A and B vaccination) are also recommended.

Critical New Recommendation

As much of the disease burden is in the “Baby Boomers,” the CDC  now recommends one time testing of all persons born between 1945 and 1965. 

Bottom Line:

While emergency department management is focused on the treatment of acute complications of liver disease, it is also important to have all age appropriate patients follow-up for testing and treatment of Hepatitis C with their primary care provider.

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Category: International EM

Title: Pediatric Emergency Care Guidelines

Keywords: Pediatric, IFEM, guidelines, international (PubMed Search)

Posted: 6/26/2013 by Andrea Tenner, MD (Updated: 4/18/2024)
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General Information:

An estimated 70 children in the world die every 5 minutes-- 99% of these deaths are from developing countries, half in Sub-Saharan Africa , and two-thirds from preventable or easily treatable causes.

Area of the world affected:

One study examining the quality of hospital emergency care of 131 children in 21 hospitals in 7 developing countries found:

·       66% of hospitals did not have adequate triage; 41% of patients had inadequate initial assessment;

·       44% received inappropriate treatment and 30% had insuf cient monitoring.

·       Frequent essential drugs, laboratory and radiology services supply outages

·       Staffing and knowledge shortages for medical and nursing personnel

 

Relevance to the US physician:

The International Federation of Emergency Medicine (IFEM) used a consensus approach to develop the International Standards for Emergency Care of Children in Emergency Departments, published in July 2012.

·       The standards covering initial assessment, stabilization and treatment, staf ng and training

·       Guidelines for coordinating, monitoring and improving the pediatric emergency care are addressed

 

Bottom Line:

The IFEM International Standards for Emergency Care of Children provide an excellent resource for both clinicians and hospital managers in developing countries.

University of Maryland Section of Global Emergency Health

Author:Terrence Mulligan DO, MPH,FIFEM, FACEP, FAAEM, FACOEP, FNVSHA

--thanks and acknowledgments to Baljit Cheema, University of Cape Town and Stellenbosch University, South Africa

 

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Category: International EM

Title: Hepatitis A Outbreak

Keywords: hepatitis A, international, food-borne illness (PubMed Search)

Posted: 6/19/2013 by Andrea Tenner, MD (Updated: 6/26/2013)
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General Information:

Hepatitis A is a food-borne illness that is prevalent in developing countries.  Currently in the US we are experiencing an outbreak in 8 states related to a frozen blend of organic berries. (Linked to Townson Farms brand sold at Costco and Harris Teeter)

Clinical Presentation:

- Case definition: sudden onset of S/S + jaundice or elevated liver enzyme levels

- S/S: nausea, anorexia, fever, malaise, abdominal pain

Diagnosis:

- Hepatitis A IgM

Treatment:

- Exposed patients should be given the Hep A vaccine within 2 weeks of exposure

- Exposed patients >40 yrs old, <1 yr old, immunocompromised, or with chronic liver disease: give immunoglobulin instead (risk of more severe disease)

- Supportive care

Bottom Line:

Patients potentially exposed to Hepatitis A in the past 2 weeks should be given either the vaccination or immunoglobulin, depending on comorbid conditions.  Treatment of active infection is supportive.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Category: International EM

Title: Listeria Infection

Keywords: Listeria, cheese, infectious disease, fever, gastroenteritis, pregnant (PubMed Search)

Posted: 6/12/2013 by Andrea Tenner, MD
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General Information:

-Listeria can cause serious infections in vulnerable groups: adults >65 years old, pregnant women, newborns, immunocompromised

-In a recent CDC report, infection with Listeria was associated with a 20% mortality rate.

Clinical Presentation:

- History of cantaloupe, soft cheese, or raw produce ingestion

- Non-specific symptoms: fever, myalgias, occasionally preceded by GI symptoms

-Can have headache, stiff neck, confusion, AMS, miscarriage or stillbirth in pregnant women

Diagnosis:

- Blood, CSF, or amniotic fluid culture showing Listeria monocytogenes

- Listeria is a reportable disease

Treatment:

- Ampicillin and Penicillin G are the drugs of choice

- Add gentamycin in CSF infection, endocarditis, the immunocompromised, and neonates.

Bottom Line:

Listeria infections have a high mortality rate and can be found worldwide.  Suspect in patients who have febrile syndromes and travel to areas where they may consume unpasteurized cheese.

 

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Category: International EM

Title: Global Health Policy--The Big Picture

Keywords: global, health, accountability, sovereignty (PubMed Search)

Posted: 6/5/2013 by Andrea Tenner, MD (Updated: 4/18/2024)
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General Information:

-The global health world is faced with an unprecedented challenge of a trio of threats:

     1. Infections, undernutrition, reproductive health issues

     2. Rising global burden of non-communicable diseases and risk factors

     3. Challenges arising from globalization (climate change and trade politics)

-Definitions of global health are variable and can emphasize anything from types of health problems, populations of interest, geographic area or a specific mission.  This makes governance and analysis difficult.

-During the past decade there has been an explosion of more than 175 initiatives, funds, agencies, and donors.  Health is increasingly influenced by decisions made in other global policymaking areas.

-The major governance challenges for global health are:

     1. Defining national sovereignty in the context of deepening health interdependence

     2. Maximizing cross-sector interdependence

     3. Developing clear mechanisms of accountability for non-state actors

Relevance to the US physician:

The Global Health System and its governance affects our ability to work effectively within the US and how we structure efforts to expand the reach of timely, effective emergency care worldwide.

Bottom Line:

The Global Health System has become more complex. Any development of Emergency Care Systems must take into account the complexity of actors in the field of global health.

The University of Maryland Section of Global Emergency Health

Author: Emilie J. B. Calvello, MD, MPH

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Category: International EM

Title: Concentration-Dependent Antibiotics

Keywords: antibiotics, concentration-dependent, infectious disease, international, levofloxacin, gentamicin (PubMed Search)

Posted: 5/1/2013 by Andrea Tenner, MD
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General Information:  Antibiotics are generally classified as time- and concentration-dependent.

Concentration-dependent antibiotics

  • Rate of kill is highly dependent on peak concentrations and is tissue-specific (generally 10x MIC needed for optimal bactericidal effect)
  • As concentrations of the drug decrease, the bactericidal effect decreases
  • Need less frequent dosing but higher doses
  • Examples:

                    -Fluoroquinolones (i.e. Levofloxacin)

                    -Aminoglycosides (i.e. Gentamicin)

                    -Azithromycin

Relevance to the EM Physician:

Concentration-dependent antibiotics should be given at the highest appropriate dose for the target tissues (i.e. Levofloxacin 750mg for pneumonia is preferable to 500mg).  This is also the rationale for high dose, extended-interval dosing for Gentamicin (>5mg/kg initial dose).

University of Maryland Section of Global Emergency Health

Author:  Andi Tenner, MD, MPH

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Category: International EM

Title: Wait--the creatinine is what?!?!?

Keywords: international, laboratory, lab values, SI, conventional (PubMed Search)

Posted: 4/24/2013 by Andrea Tenner, MD
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General Information:

The two main units used by medical laboratories are "conventional (used in the US) and SI (used by most other countries).

Pearls to know:

  • For monovalent ions (i.e. Na+, Cl-) -- mEq/L=mmol/L (135 mEq = 135 mmol/L)
  • For divalent ions (i.e. ionized Ca2+, Mg2+) -- mEq/2=mmol (Mg2+ of 2 mEq/L = 1 mmol/L)
  • Creatinine -- Multiply conventional untis by 88 (1 mg/dL = 88 mmol/L)
  • Glucose -- Multiply SI units by 18 (4 mmol/L = 72 mg/dL)
  • Hemoglobin--Multiply conventional units by 10 (14 g/dL = 140 g/L)

Relevance to the EM Physician:

These tips will help you convert labs to familiar values when reading medical literature, when working in another country, or when working with international colleagues.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Category: International EM

Title: New SARS-Like Virus

Keywords: novel, coronavirus, International, infectious, SARS, pulmonary (PubMed Search)

Posted: 3/19/2013 by Andrea Tenner, MD (Emailed: 3/20/2013) (Updated: 3/25/2013)
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General Information:

14 cases of lower respiratory infection caused by a new coronavirus (not the original SARS virus, but with a similar picture) occurred in the past year.  Mortality rate of this virus is >50%.

Area of the world affected:

  • Arabian Peninsula
  • United Kingdom

Relevance to the US physician:

  • Suspect this with a lower respiratory tract infection not responding to therapy and a travel history
  • Person to person transmission possible
  • Can have coinfection with influenza
  • PCR testing can be done at the CDC in suspected cases

Bottom Line:

Consider this infection in patients with a lower respiratory tract infection who have traveled to or had contact with someone who traveled to the above regions in the past 10 days.

ASK ABOUT RECENT TRAVELS IN PATIENTS PRESENTING WITH SYMPTOMS OF SEVERE LOWER RESPIRATORY TRACT INFECTION!

University of Maryland Section of Global Emergency Health

Author:  Veronica Pei MD, MPH

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Category: International EM

Title: Saving lives in a disaster

Keywords: disaster, Sphere, international, sanitation, hygiene, infectious disease, water (PubMed Search)

Posted: 2/27/2013 by Andrea Tenner, MD
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Background Information:

Ever wonder what you would do if you were the first on scene after the earthquake in Haiti or in the Superdome as Hurricaine Katrina survivors started to arrive? How could you save the most lives? As is typical of emergency medicine, blood and gore tend to get the most attention, but if you want to save lives you have to think about what is the greatest life threat.  In a large-scale disaster, it turns out, lack of water and abundance of feces kill the most the fastest and need to be addressed first.

The Sphere Project Handbook:

-one of the core documents of humanitarian response

-outlines what should be done to save the most lives in the first days, weeks, and months of a disaster.

-available free online (see reference below)

Pertinent Conclusions: (need-to-know recommendations for the first few days)

-Water: 15L/person/day (any quality--sanitize as per our previous pearl)

-Latrines: max 20 people/latrine, <50m from dwellings, >30m from water sources

       -What kind?

             -First 2-3 days: demarcated defecation area

             -days-2 months: trench latrines (shallow trenches to defecate in)

Other hygeine:

-Solid waste disposal: one 100L refuse container/10 households, emptied at least 2x/week

-Dead bodies: dispose of according to local custom. Generally not an immediate source of infection

-Shelter: >3.5 sq. meters/person of covered floor space

Bottom LIne:

People's need for water and defecation will not stop in a disaster and too little water and too much excrement are the greatest immediate life threats to disaster survivors. Plan to deal with these early to save the most lives.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Category: International EM

Title: Japanese Encephalitis

Keywords: japanese encephalitis, international, virus, infectious disease (PubMed Search)

Posted: 2/20/2013 by Andrea Tenner, MD (Updated: 4/18/2024)
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Japanese Encephalitis

 
General Information:
     – caused by Japanese encephalitis virus (JEV), closely related to West Nile virus    
     – transmission is through infected mosquito
     – most common cause of vaccine-preventable cause of encephalitis in Asia
     – Incubation period is 5-15 days
     – <1% develop clinical, disease, most asymptomatic
     – Acute encephalitis most common presentation 
     – Sx: altered mental status, focal neuro deficits, movement disorder, seizure, fever, headache,    
         vomiting
     – Classic presentation: Parkinsonian syndrome with mask-like facies, tremor, cogwheel rigidity, and
        choreoathtoid movements
     – case-fatality is 20-30%
 
Area of the world affected:
     -- Primarily in Asia – China, Japan, Korea, India, Southeast Asia
 
Relevance to the US physician:
1. JE
      -- Should be considered in patients concerned for neurological infection with recent travel to
          endemic country
      -- Lab: JEV-specific IgM in serum (after 7 days of sx onset) or CSF (after 4 days of sx onset)
      -- Viral culture and other viral RNA amplifications tests are not sensitive
      -- Treatment is supportive
      -- In survivors, 30-50% have significant neurological/cognitive/psychological sequelae
2. Vaccine
      -- One vaccine (Ixiaro) is available in the US    
      -- 2 doses, 28 days apart (96% develop immunity)
      -- No information on duration of protection
      -- Recommended for travelers ≥ 1 month in endemic areas during JEV season
 
Bottom Line:
Very rare but deadly disease with high mortality and post-infection sequelae.  Think about it in travelers to Asia during summer/fall seasons who have not been immunized.
 
University of Maryland Section of Global Emergency Health
Author:  Veronica Pei
 

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Category: International EM

Title: Clarification: Melioidosis

Keywords: Melioidosis, Burkholderia pseudomallei (PubMed Search)

Posted: 2/7/2013 by Andrea Tenner, MD (Updated: 4/18/2024)
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Just a quick clarification to last week's melioidosis pearl:

An astute reader noted the typo:  "The patient should also be covered for melioidosis, and infection caused by Burkholderia pseudomallei."  The sentence should read "...meliodosis, an infection caused by Burkholderia pseudomallei."

Just to clarify, melioidosis is caused by the bacteria Burkholderia pseudomallei.

Many apologies for any confusion this might have caused.

Thanks for reading!

Andi Tenner, MD, MPH



Category: International EM

Title: PPD positive? Good news...

Keywords: Rifapentine, latent tuberculosis, international, infectious disease (PubMed Search)

Posted: 2/6/2013 by Andrea Tenner, MD (Updated: 4/18/2024)
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Background Information:

Active tuberculosis (TB) develops in 5-10% of individuals who become infected with M. tuberculosis, typically after a latency period of 6-18 months (but sometimes decades later).  Compliance with the 9 month self-supervised isoniazid (INH) regimen has been porr with completion rates <60%.  Until recently, daily rifampin for 4-6 months has been the only alternative when the bacterium is resistant or INH cannot be used.

Pertinent Study Design and Conclusions:

  • Another rifamycin class antibiotic, Rifapentine (RPT) is approved for MDR-TB but had not been approved for latent TB treatment.
  • Recent RCTs show 12 weekly doses of INH-RPT administered as directly observed therapy (DOT) are efficacious in preventing active disease and are better tolerated.
  • CDC now recommends the 12 week INH-RPT DOT regimen as an equal alternative to 9 months of self supervised daily INH in patients aged >12 years who have a high likelihood of developing active TB.

Bottom LIne:

A substantially shorter course of therapy with INH-RPT is now the recommended treatment for latent TB.

University of Maryland Section of Global Emergency Health

Author: Emilie J. B. Calvello, MD, MPH

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Category: International EM

Title: Imported Pneumonia--what to worry about?

Keywords: melioidosis, pneumonia, Thailand, international, infectious disease (PubMed Search)

Posted: 1/30/2013 by Andrea Tenner, MD
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Case Presentation:

A 43 year old diabetic woman presents with dyspnea and a dry cough. Her vital signs are:  BP 84/42, HR 135 RR 37 T 38.5.  Lobar consolidation is seen on chest xray.  She decompensates and is intubated, a central line is placed, and IV fluids are started.  Her husband reports that they had just returned from  a vacation in Thailand one week earlier.

Clinical Question:

Does the recent travel change your choice of empiric antibiotics?

Answer:

The patient should also be covered for melioidosis, and infection caused by Burkholderia pseudomallei.

  • Infection can occur via direct contact with, inhalation of, or ingestion of the bacteria.
  • B. pseudomallei is highly endemic in Thailand and Northern Australia, but melioidosis has been contracted in the Americas and other parts of Asia and Australia. (True epidemiology is unknown due to difficulties in culturing the bacteria)
  • Clinical presentation most frequently involves pulmonary infection, abscess formation, or bacteremia.
  • Labs that don't have experience with this bacteria have difficulty culturing it and it is often misidentified.
  • Treatment is 10-14 days of ceftazidime or a carbapenem.
  • After recovery, the patient requires TMP-SMX for 3-6 months for bacterial eradication. 

Bottom Line:

Patients presenting with severe infections and recent travel to an endemic area should receive emperic antibiotics with ceftazidime or a carbapenem until another source is identified. 

University of Maryland Section of Global Emergency Health

Author: Jenny Reifel Saltzberg, MD, MPH

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Category: International EM

Title: A not-so-uncommon cause of seizure....

Keywords: neurocysticercosis, seizure, Taenia, tapeworm (PubMed Search)

Posted: 1/23/2013 by Andrea Tenner, MD
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Question

A 38 year old man is brought in by ambulance for a seizure.  His medical history is not known. On exam he is post-ictal and otherwise has a non-focal neurologic exam.  He has an abrasion above the right eye, a small tongue laceration, and was incontinent of urine. A head CT was done and is shown below.  What was the cause of this man's seizure?

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Category: Visual Diagnosis

Title: Spinal Deformity

Keywords: spinal, international, tuberculosis, scoliosis, kyphosis, pulmonary, neurologic (PubMed Search)

Posted: 1/9/2013 by Andrea Tenner, MD
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Question

These two Ethiopian boys present with “back problems”.  What are the diagnoses and what do you need to worry about with each of them?

 

 

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Attachments

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Category: International EM

Title: Leptospirosis

Keywords: Leptospirosis, Baltimore, jaundice, thrombocytopenia, international, tropical (PubMed Search)

Posted: 1/2/2013 by Andrea Tenner, MD
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General Information:

-Leptospirosis is a tropical infectious disease that is also endemic in the US. (Estimated 16% seroprevalence in inner city Baltimore!)

-The spirochete is spread through animal urine and can survive in water or soil for weeks.

-Risk factors: rural exposure to animal urine (farming, adventure sports) or urban exposure to rat urine.

-Infection is acquired through breaks in the skin or mucus membranes

-Outbreaks are often seen following rain or floods. 

Clinical Presentation:

-Non-specific febrile illness (usually not diagnosed in these cases)

-If untreated, 5-10% progress to jaundice, renal failure, thrombocytopenia, hemorrhage, and respiratory failure.

Diagnosis:

- Primarily based on clinical presentation and history

- Paired serum sent to CDC (the acute serum sample should be drawn in the ED)

Treatment:

- Doxycycline, Ceftriaxone and Penicillin are all effective

Bottom Line:

Consider and treat for Leptospirosis in patients with possible exposure animal urine (especially after a flood) who present in extremis with renal failure, jaundice, and thrombocytopenia.

University of Maryland Section of Global Emergency Health

Author: Andi Tenner, MD, MPH

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Category: International EM

Title: Dengue

Keywords: dengue, fever, international, mosquito, vector (PubMed Search)

Posted: 12/12/2012 by Andrea Tenner, MD (Updated: 4/18/2024)
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Background:

Dengue is the most rapidly expanding mosquito-borne virus with an increasing incidence and geographical area.  It is most commonly found in the tropics, but there are occasional outbreaks in other places, including Texas and Hawaii.

Clinical:

Three Phases:

1.  The febrile phase lasts 2-7 dyas and is similar to other viral syndromes, often with high fever and nausea/vomiting.  Petechiae may also be present which can be induced by the application of a tourniquet.

2. The critical phase occurs after defervescence and lasts only 24-48 hours. IT is marked by increased capillary permeability and can lead to severe pulmonary edema, shock, and multisystem organ failure.

3. The recovery phase is marked by hemodynamic improvement. Some patients have a rash described as "isles of white in a sea of red." 

Some patients will develop bradycardia. Most patients have a self-limited form of the illness that is not severe, and consists of symptoms seen in the febrile phase.  The patients that develop severe dengue can have markers in the febrile phase that are associated with organ dysfunction, GI bleeding, and increased capillary permeability. Other concerning symptoms early are abdominal tenderness and persistent vomiting.

Treatment:

Treatment is supportive, mostly consisting of IV fluids, which is very effective when started early in the patient's illness.  For more information and maps of endemic areas check out the CDC or WHO websites:  http://www.cdc.gov/travel/notices/in-the-news/dengue-tropical-sub-tropical.htm or http://www.who.int/denguecontrol/en/

University of Maryland Section for Global Emergency Health

Author: Jenny Saltzberg

 

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Category: International EM

Title: When Water is Undrinkable

Keywords: water, international, cryptopsporidium, chlorine, iodine, boiling (PubMed Search)

Posted: 11/28/2012 by Andrea Tenner, MD
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General Information:
• Millions of people around the world (including our patients who travel and victims of disasters like Hurricane Sandy) are exposed to non-potable water.
• How to treat contaminated water:
      ♦ Filter cloudy water through a clean cloth or allow to settle prior to treatment
      ♦ The safest method is boiling water vigorously for 1 minute (or, at least 3 minutes at altitudes >6,000ft)
      ♦ Chemical disinfection is not as effective but, if boiling is not possible, use either:
              • 2 drops of unscented bleach (5.52% Cl) per quart/liter of water.  (Unknown strength? Add 10     drops per quart/liter.)
                -Or-
               • 5 drops of tincture of 2% iodine per quart/liter.
                     - If the water is cloudy or cold, double the chlorine or iodine.
                     - Notes: Pregnant women or people with thyroid conditions should not use iodine
       ♦ UV decontamination can be accomplished by leaving clear bottles of water in direct sun for >6 hours or special equipment, but requires clear water
• Boiling, Chlorine/Iodine, and UV will kill viruses, bacteria, and Giardia
• Only Boiling kills Cryptosporidium

Bottom Line:
• If bottled water is available, use it.
• If not, boil your water.
• In order to treat for a wide variety of pathogens, it is best to combine available methods.

University of Maryland Section for Global Emergency Health
Author: Andi Tenner
 

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