The ASCO clinical practice guideline for antimicrobial prophylaxis and outpatient management of fever and neutropenia; Use in those exposed to ionized iradiation

The American Society of Clinical Oncology published their clinical practice guideline for antimicrobial prophylaxis and outpatient management of fever and neutropenia in adults treated for malignancy. The guidelines were based on 43 studies.

These were the recommendations: Antibacterial and antifungal prophylaxis are only recommended for patients expected to have < 100 neutrophils/μL for > 7 days, unless other factors increase risks for complications or mortality to similar levels. Inpatient treatment is standard to manage febrile neutropenic episodes, although carefully selected patients may be managed as outpatients after systematic assessment beginning with a validated risk index (eg, Multinational Association for Supportive Care in Cancer [MASCC] score or Talcott's rules). Patients with MASCC scores ≥ 21 or in Talcott group 4, and without other risk factors, can be managed safely as outpatients. Febrile neutropenic patients should receive initial doses of empirical antibacterial therapy within an hour of triage and should either be monitored for at least 4 hours to determine suitability for outpatient management or be admitted to the hospital. An oral fluoroquinolone plus amoxicillin/clavulanate (or plus clindamycin if penicillin allergic) is recommended as empiric therapy, unless fluoroquinolone prophylaxis was used before fever developed.

Even though the principles behind these guidelines are similar to the ones used for the treatment of individuals who developed neutropenia after exposure to ionized radiation, caution should be used in implementing these guidelines for those who were irradiated. There is a risk in using antimicrobials effective against anaerobic bacteria (amoxicillin/clavulanate or clindamycin) in individuals exposed to ionizing radiation as studies in rodents illustrated the developmentof early sepsis in those treated with such agents. 

Neutropenia

A Nuclear Storage Tank In Washington StateIs Leaking Radioactive Waste

Jay Inslee, the governor of Washington state reported on February 15 that a tank storing radioactive waste at the Hanford Nuclear Reservation is leaking liquids about 150 to 300 gallons per year. The governor stressed that the leak poses no immediate public health.

The tank was built in the 1940s and holds about 447,000 gallons of sludge. The Hanford site houses 177 tanks, 149 of which are single-shell tanks. Twenty- eight of those tanks have double walls, allowing the Energy Department to pump waste from leaking single-shell tanks into them. However, there is very little space left in those double-shell tanks today. The leaking tank is believed to be the first to lose liquids since 2005.

The Hanford site is a 586-square-mile area that once played a major part in U.S. plutonium production. The federal government created Hanford at the height of the second World War in the remote sagebrush of eastern Washington State as part of a secret project to build the atomic bomb. The site ultimately produced plutonium for the world's first atomic blast and for one of two atomic bombs dropped on Japan, effectively ending the war. The site is now home to one of the largest nuclear cleanup efforts in the world.

Plutonium production continued there through the Cold War. Currently, Hanford is the most contaminated nuclear site in the US. Cleanup will cost billions of dollars and last decades.

The Hanford Storage site

Radiation exposure to workers at Fukushima

The Japanese Association for Acute Medicine Emergency Task Force on the Fukushima Nuclear Power Plant Accident recently released an article in Emergency Medicine Journal Online First describing the initial medical response. 

A total of 261 patients were seen by the Task Force, eight of whom had external radiation contamination.  Six of these were workers whose exposure doses from March 2011 to February 2012 exceeded the annual dose limit of 250 mSv. The highest external exposure recorded was 110 mSv and the highest internal exposure (probably from iodine-131) was 590 mSv. Importantly, none of the patients developed symptoms associated with acute radiation syndrome/sickness (ARS). The threshold for the hematopoietic syndrome of ARS is considered to be 1 Gy (1000 mSv equivalent).

Fukushima Nuclear Power Plant workers

Early detection of radiation exposure

Scientists at the Lawrence Berkeley National Laboratory are currently working on a new way of rapidly detection of radiation exposure. They have identified eight DNA-repair genes whose expression response to radiation changes in less than half of the time that detection was possible in the past. Since many genes alter their expression after radiation exposure to both radiation and inflammation, they looked carefully to see how the genetic response varies between these two causes. They compared their findings in samples taken from patients undergoing whole-body irradiation prior to bone marrow transplantation and the results confirmed their findings. More work is needed but the chances of finding a blood test that could be rapidly administered and analyzed in the field by emergency responders are improved.  This would be particularly helpful in patients with combined injury, whose care and prognosis differs from patients receiving burns or trauma alone, particularly at higher doses.

 Lawrence Berkeley National Laboratory  in the San Fransisco Bay area in California

Radioactive water leakage at Japan's damaged Fukushima Dai-ichi nuclear power

Japan's damaged Fukushima Dai-ichi nuclear power plant is struggling to find room to store tens of thousands of gallons of highly contaminated water used to cool the broken reactors. Large volume of radioactive water, enough to fill more than 50 Olympic-sized swimming pools, are being stored in hundreds of large tanks built around the plant.

Operator Tokyo Electric Power Company has already cut down numerous trees to make room for more tanks and predicts the volume of water will be more than triple within three years. Dumping massive amounts of water into the melting reactors was the only way to avoid an even bigger catastrophe. The measures to keep the plant under control created another major problem for the utility: What to do with all that radioactive water that leaked out of the damaged reactors and collected in the basements of reactor buildings and nearby installations.

Even though the reactors are currently being cooled only with recycled water, the volume of contaminated water is still increasing, because ground water is seeping through cracks into the reactor and turbine basements.  The Power Company is setting up a treatment system that would make the water clean enough for reuse as a coolant thus reducing health risks for workers and environmental damage. There is, however, concern hat the radioactive water in the basements may get into the underground water system, where it could reach far beyond the plant through underground water channels, possibly in the ocean or public water supplies.

A study About The Radiation Exposure After the Fukushima Nuclear Power Plant Disaster

The first study in Japanese that reside near the Fukushima nuclear plant damaged by the March 2011 earthquake and tsunami found low levels of radiation exposure were found. The study was published today in the Journal of the American Medical Association. The average radiation was "well under" under 1 millisiever, considered a safe dosage.

The study was conducted between September 2011 and March 2012, and the researchers measured levels of radioactive cesium in 8,066 adults and 1,432 children in Minamisoma, about 14 miles north of the Fukushima Daiichi power plant. About a-third of the residents tested - 235 children and 3,051 adults - had detectable cesium radiation.

According to Roy Shore, the chief of research at the Radiation Effects Research Foundation in Hiroshima, Japan, the expected impact of the public health impact of the accident will be lower than that of Chernobyl.

. However, the radiation had affected at least one other species: butterflies. Investigator found that three generations of pale grass blue butterflies suffered genetic mutations as a result of Fukushima fallout.

Another report found that because of discriminatory attitudes against them, Tokyo Electric Power Co. employees at the Fukushima Daiichi plant and its nearby companion, Fukushima Daini, are suffering depression and other mental illnesses two times more than other Japanese.

Fukushima nuclear power workers

World Health organization releases Fukushima radiation report

The preliminary report from the World Health Organisation (WHO) report published on May 23, 2012 stats that radiation levels in most of Japan are lower than cancer-causing levels a year following the Fukushima plant accident. While two areas close to the plant have relatively higher levels of radiation, but radiation levels in surrounding countries are almost normal.

A different finding from a UN scientific committee stated that several workers at the Fukushima plant had been "irradiated after contamination of their skin". The statement issued as interim findings by the United Nations Scientific Committee on the Effects of Radiation (UNSCEAR) was that "Six workers have died since the accident but none of the deaths were linked to irradiation".

Namie town and Itate village, that are close to the Fukushima plant in eastern Japan, are currently exposed to radiation levels of 10-50 millisieverts (mSv), while the radiation levels at the rest of Fukushima are 1-10 mSv, the WHO report said. Most of Japan has levels of 0.1-1 mSv, while neighbouring countries have less than 0.01 mSv.

These findings should be assessed taking into consideration that the single-year limit for occupational exposure of workers is 50 mSv. Most individuals are exposed on average to around 2 mSv of radiation a year from the natural environment.

Airial view of the Fukushima power plant