Meningococcemia

What is Meningococcemia?

Bacteremia is a serious infectious disease that can occur in children, which can lead to septic shock, a life-threatening condition that happens when toxins from an infection enter the bloodstream and impair the blood flow to various body tissues. One common cause of this condition is Neisseria meningitidis, a bacterial infection that often results in meningitis (an infection of the brain and spinal cord coverings) or septicemia (a severe infection in the blood), or a combination of both.

The infection starts with bacteria colonizing the throat without causing symptoms, with humans being the primary carriers. The bacteria then travels from the throat through routes like along the protective covering of the smelling nerve, reaching the brain structures. If the bacteria spreads to the brain through the bloodstream, it can cause meningitis. In some children, the main issue is a severe drop in blood pressure leading to septic shock.

The bacteria is spread through respiratory droplets when an infected person coughs or sneezes and it requires close contact. Young children under five years old are more susceptible because their immune systems aren’t fully developed to fight the bacteria. Other risk factors include inadequate immune resistance, lack of awareness about the disease and poor hygiene practices, natural closeness among children, and common mouth contact with shared objects.

Severe meningococcal disease affects mainly two age groups: infants, who are at risk because their mother’s protective antibodies worn off early in life, and teenagers, who often have a high rate of bacteria colonization in their throat.

What Causes Meningococcemia?

N. meningitidis is a certain type of bacterium. The bacterium is essentially made up of pairs of rounded or spherical particles, with the sides that are facing each other appearing to be flat. This bacterium doesn’t move by itself. It can live in environments with and without air. It produces two types of enzymes, catalase and oxidase. This bacterium also produces acid from two types of sugars: glucose and maltose.

When this bacterium is freshly isolated or newly taken from a patient’s body, it needs to be placed in a rich-environment or nutrient packed substance like blood or chocolate agar to grow. The growth of this bacterium is enhanced in a warm, moist environment with a small amount of carbon dioxide in it.

This bacterium has a few ways in which it can cause harm. It has a coating made of a sugary material which aids in its ability to invade human cells and allows it to survive when it enters the blood and brain. Another one is that it grows hair-like structures or filaments which help it to attach, settle, and invade the lining of the upper part of the throat, behind the nose. The bacterium has a way of altering these filaments to avoid detection by the immune system.

There are several proteins on its outer surface that this bacterium uses for different purposes. Some proteins act like tiny gates that can insert themselves into the walls of target cells, causing the cells to self-destruct. Other proteins help in the attachment to and invasion of the lining of body passages and blood vessels. There is also an enzyme that breaks down a type of immune system molecule at body surfaces, enabling initial attachment and invasion.

This bacterium can survive and multiply using a mechanism to extract iron from proteins that hold onto iron. It also has the ability to become resistant to penicillin by absorbing the genetic material of other harmless bacteria present in the throat. It can change its surface appearance, avoiding detection by the immune system.

The bacterium’s sugary coating is specific to its type, and forms the basis of assigning it to different groups. There are twelve groups in all, named alphabetically from A to Z, including W-135 and 29F. The most common types causing serious disease worldwide are A, B, C, W-135, X, and Y.

Risk Factors and Frequency for Meningococcemia

In the United States, invasive infections from N. meningitidis are tracked and reported by the National Notifiable surveillance system. The lowest numbers of these cases, 556 and 564, were reported in 2013 and 2014, respectively. The incidence of this disease was 0.14 per 100,000 people in the country in 2014. Of the reported cases, 25% had bacteremia with a mortality rate of 20%. Regarding the type of serogroup responsible for the disease, 26% was due to serogroup B, 36% from serogroup C, 9% by serogroup Y, and 28% by other serogroups. The disease normally peaks between November and March, with an increase in protective antibodies against the bacteria occurring in children aged between 2-12 years.

In contrast, developing countries have a higher incidence rate of 10 to 25 per 100,000 people per year. The highest rate, between 10 and 1000 per 100,000 annually, is seen in sub-Saharan Africa (also known as the meningitis belt) due to recurrent epidemics of group A. There have also been some outbreaks of a strain relatively rare in Africa, meningococcal serogroup C, in Nigeria and Kebbi in 2013 and 2014.

There have also been outbreaks related to the Hajj pilgrimage to Mecca, with an outbreak in 1987 due to serogroup A and in 2000 due to serogroup W-135. This group has also begun to appear in other regions, such as South America and England. In Europe, there has been a decline in invasive serogroup C disease, with serogroup B causing 60% to 72% of invasive disease cases. In Asia, there have been large epidemics historically caused by serogroup A in countries such as China, India, Nepal, and Russia. Recently, serogroups B and C have emerged as the cause in this area. There has also been an increase in serogroup Y reported in Nordic European countries.

Signs and Symptoms of Meningococcemia

N. meningitidis is a bacterium that can cause a range of health conditions, from showing no symptoms at all to causing severe, potentially fatal diseases. The most common serious conditions caused by this bacterium are meningitis and septicemia, which is blood poisoning. Some patients may show both types of these symptoms.

The symptoms of meningococcemia often begin with an upper respiratory tract infection, including symptoms such as a stuffy nose, sore throat, tonsillitis, and laryngitis. The patient will often have a fever, headache, vomiting, and feel lethargic. A notable symptom of meningococcemia is a fever and a bleeding rash, which can lead to signs of serious circulatory system failure. A purplish rash and shock can develop within hours of the first symptoms. Different forms of skin rashes are seen, from a blotchy pattern to extensive bleeding rashes. Half to over half of patients will have small red or purple spots or larger patches. However, between 20% to 30% of children may not have any rash when they first see a doctor.

Chronic meningococcemia is a form of the disease where the patient has a fever for at least a week before receiving antibiotic therapy and does not show symptoms of meningitis. In these cases, we do not find bacteria when testing skin rashes or by biopsy. Researchers believe that the skin changes and arthritis-like symptoms may be caused by the body’s immune response to the bacteria. The diagnosis is often made by identifying the bacterium in blood tests. The condition typically resolves quickly following antibiotic therapy.

Researchers have highlighted heart-related problems linked to meningococcal meningitis, such as heart failure with fluid build-up in the lungs and high pressure in the central veins accompanied by poor blood flow to the rest of the body. Treatment of the heart failure can improve the condition. High levels of a substance called interleukin 6 could be contributing to heart weakness in patients with septic shock due to a meningococcal infection.

Testing for Meningococcemia

When a doctor suspects an infection, they often diagnose it based on symptoms and begin treatment with antibiotics. The antibiotics will combat a broad range of bacteria while the doctor works to identify the specific disease-causing organism.

In the lab, medical professionals test samples from your body to find out exactly what’s causing the infection. They do this for three main reasons: to ensure public health safety, to determine which antibiotics are effective against the bacteria, and to confirm whether or not other organisms are causing the infection.

There are a few key tests that can be done. One of these is a Gram stain. This test is applied to a sample of cerebrospinal fluid, which is the clear, protective fluid that surrounds your brain and spinal cord. In the case of an infection with meningitis, the Gram stain will show specific types of bacteria.

Another important test is the culture. The cerebrospinal fluid is spread onto a special plate – called a chocolate agar – and left in a controlled atmospheric condition to grow. This can allow the specific organism causing the infection to be identified. Blood samples can also be cultured to find the bacteria. Coupling the results of these blood and cerebrospinal fluid cultures with the Gram stain result can help identify the exact bacteria causing meningitis in about 94% of cases.

Other tests can be done to detect bacterial antigens, which are substances that trigger an immune response. These tests, like latex agglutination or PCR assays, can be done on cerebrospinal fluid or blood. The latter is particularly reliable, with an accuracy rate well over 90%. They are also quick, giving results within a few hours. Importantly, PCR assays are still effective even if treatment with antibiotics has already started.

If needed, the doctor may decide to do a brain scan, called a CT (computed tomography) scan. This is especially useful if the patient is in a coma and the doctor needs to rule out bleeding in the brain.

Finally, blood tests can also indicate an infection by showing an increased number of white blood cell, which help to fight infections. Proteins such as C-reactive protein can also be traced in the blood, signifying the body’s response to inflammation. The doctor would also look for other signals like low glucose levels and alterations in cell types.

In severe cases of meningococcal septicemia, where the bacteria have entered the bloodstream, several life-threatening metabolic changes can occur. These include changes in blood sugar, potassium, calcium, magnesium, and phosphate levels. There may also be anemia, clotting issues, and lower levels of specific clotting factors. These changes demand swift attention and treatment.

Treatment Options for Meningococcemia

Antibiotics like ceftriaxone, cefotaxime, penicillin G, chloramphenicol, or meropenem (for those with severe allergies) may be used to treat ongoing infections. The treatment typically lasts 7 days and may be given by a drip into a vein (intravenously) or orally (by mouth). This is the case for both meningitis and another serious condition called meningococcemia which is a type of blood poisoning.

Another possible treatment is corticosteroid therapy, which can help children who have refractory shock – a severe and oftentimes fatal condition where the body is not responding to treatment and blood pressure remains low. It’s linked with a condition where the adrenal glands, which make important hormones, aren’t responding as they should.

There’s also an experimental treatment called “recombinant bactericidal permeability-increasing protein” (rBPI). This treatment works by binding to a toxic part of bacteria called endotoxin and stopping the process that leads to inflammation. Children receiving rBPI have had fewer amputations, needed fewer blood transfusions and showed improved functional outcomes.

Other experimental treatment methods include plasmapheresis (a process to cleanse the blood of harmful substances), ECMO (a type of life support that helps the heart and lungs), fibrinolysis (a process to prevent blood clots), and anti-mediator therapy (medicines to modify the body’s immune response).

If a child has a condition called meningococcal disease, emergency medical care entails securing the child’s airway and then focusing on two main things. The first is correcting cardiovascular shock – a life-threatening medical condition where not enough blood is supplied to the body, leading to organ failure – and the second is managing raised intracranial pressure – a condition where there is a buildup of pressure inside the skull.

The child may be given fluids quickly (aggressive fluid resuscitation) through a drip into a vein to help improve their condition. This initial treatment may be repeated until their condition improves. To maintain the right blood flow to their body tissues (tissue perfusion), medical support may be needed. Human albumin solution, a type of protein, may also be used.

Medical staff will also monitor for and correct conditions like anemia (low number of red blood cells) and coagulopathy (a condition where the blood’s ability to clot is impaired). If the brain is under too much pressure, medical staff will ensure that enough blood is reaching the brain by correcting shock and providing intensive care for the brain.

What else can Meningococcemia be?

There are several possible causes of certain symptoms that can be classified as either infectious or non-infectious. Infectious causes may include:

• Rocky Mountain spotted fever
• Ehrlichiosis
• Streptococcal pneumoniae
• Hemophilus influenza type B
• Group A streptococcus
• Staphylococcus aureus
• Gram-negative bacterial sepsis with DIC
• Infective endocarditis
• Gonococcemia
• Rat-bite fever
• Typhus
• Secondary syphilis

On the other hand, non-infectious causes might be:

• Henoch-Schonlein purpura
• Acute hemorrhagic edema of infancy
• Platelet disorders (such as idiopathic thrombocytopenic purpura)
• Collagen vascular diseases
• Neoplastic processes

What to expect with Meningococcemia

Scoring systems or models have been developed to predict outcomes in cases of meningococcal disease, which is a severe and potentially deadly infection. These systems often highlight two conditions – purpura fulminans (a severe rash caused by bleeding under the skin) and shock – as signs that a patient may have a poor outcome.

The Glasgow Meningococcal Septicemia Prognostic Score (GMSPS) looks at seven key factors to predict outcomes. These include low blood pressure, difference in temperature between the skin and the body’s core, coma, sudden worsening of the condition, lack of signs of meningitis, progressive purpura fulminans, and a condition called base deficit which indicates if there is too much acid in the body’s fluids.

A study at the Los Angeles Children’s Hospital identified five factors associated with a poor outcome in children: shock or seizures, low body temperature, total white blood cell count below 5000 per cubic millimeter (suggesting the body is having trouble fighting the infection), a platelet count below 100,000 per cubic millimeter (which can affect blood clotting), and the development of purpura fulminans.

The overall mortality rate for invasive meningococcal disease – which is when the disease spreads through the bloodstream – in the United States falls between 7% to 19%. A review of meningococcal deaths in the United States from 1990 to 2002 recorded 3335 deaths due to this disease.

Possible Complications When Diagnosed with Meningococcemia

: The consequences of meningococcemia, an infection in the bloodstream, can vary greatly. These might include skin damage due to tissue death, loss of hearing or complete deafness, the occurrence of seizures, the necessity for amputation, and skin scarring. Some complications are due to diminished blood flow throughout the body, such as blood vessel constriction or a failing heart leading to kidney failure. This might show up as decreased urine output or no urine at all, or potentially serious kidney failure.

Other issues may arise as a response from the body’s own immune system. For example, arthritis, skin inflammation in the blood vessels, eye inflammation, and heart sac inflammation (around the heart) can all occur due to the body’s immune response causing sudden inflammation.

Common Consequences:

• Skin damage (from tissue death)
• Hearing loss or deafness
• Seizures
• Amputations
• Skin scarring
• Kidney failure (due to decreased blood flow or a failing heart)
• Decreased or absent urine output
• Arthritis (from body’s immune response)
• Skin inflammation in the blood vessels
• Eye inflammation
• Heart sac inflammation