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BRITISH BROADCASTING CORPORATION
RADIO SCIENCE UNIT
CASE NOTES
Programme No. 9 - Meningitis
RADIO 4
TUESDAY 30/10/07 2100-2130
PRESENTER:
MARK PORTER
CONTRIBUTORS:
SIMON KROLL
DAVID INWALD
PARVIZ HABIBI
SONIA BROADBY
PRODUCER:
ERIKA WRIGHT
NOT CHECKED AS BROADCAST
KANE
It was a normal Wednesday morning in 1998 in January, I'd gone to work, I'd left Patrick at home with the nanny and he'd been a bit irritable and restless overnight but nothing serious. It was at lunchtime that day when I received a call from the nanny saying that he'd been sick a couple of times that morning - he was only nine months old, so you expect children to be a bit sick - but she said she was a bit concerned about him, so I made an appointment for him to see the doctor who immediately recognised something was wrong but he didn't know what was wrong. It was at that point she phoned me and said it had been recommended that he was taken to St Mary's Hospital in Paddington, the unbooked clinic, so they could have a look.
PORTER
Emma Kane's son Patrick was nine months old when she rushed him to St Mary's Hospital in London where her worst fears where confirmed - he had meningitis - the subject of today's special edition of Case Notes.
Simon Kroll is Professor of Paediatrics and Molecular Infectious Diseases at St Mary's.
KROLL
Meningitis is an infection, an infection of the meninges, which are the membranes covering and lining the brain. The germs that cause meningitis get there generally, it's believed, by spreading through the bloodstream and the bacteria responsible are most commonly those that are found harmlessly colonising the nose and the throat of perfectly healthy people. Occasionally for reasons that we don't understand those bacteria can invade and spread through the body and if that spread continues unchecked they can reach the meninges and set up the inflammation that is the beginning of meningitis.
PORTER
Do we know what proportion of the population carry one or other forms of these bacteria?
KROLL
Well they're very common, the carriage rate varies with age but, for example, the meningococcus which is responsible for meningococcal meningitis, one of the common and very feared varieties, is carried by 30-40% of young adults, for example. But carriage is very common, the diseases are very rare.
PORTER
And do we know what factors might identify an increased risk of a carrier becoming a victim?
KROLL
The straightforward answer to that really is no. There are some individuals, but very rare, who have particular disorders that make them more likely to get these infections. But actually the few unlucky individuals who do develop this infection are very, very much the minority - they're a tiny proportion, we're talking about perhaps 2, 3, 4 per 100,000 as opposed to the 30 or 40% who might carry the germ. And it's largely, I think, just very bad luck.
PORTER
What about the seasonal variation in infections, is there a clue there?
KROLL
The process of invasion seems - and this is a statement based on epidemiological information - seems to be enhanced by those circumstances where there's some inflammation perhaps at the back of the throat. So the time of the year, in the winter, when we have more viral infections, more colds, there does seem to be more meningitis. Having said that in the dry parts of the world, in the Sub-Saharan Africa for example, for example, it's in the dry season when the back of the membranes at the back of the throat maybe inflamed and dried out when invasion may happen more easily.
PORTER
Who gets meningitis and when?
KROLL
There's a public perception which is pretty much correct that meningitis and septicaemia, which is the other infection these bacteria causes, largely a disease of previously healthy children. There are good reasons for that. What keeps the bacteria in check in normal healthy people is a well developed immune system and it takes time for immunity to these germs to develop, in fact that immunity develops with carriage - with the germs being at the back of the nose and throat. So it's in the youngest children in particular who may encounter the germs for the first time and have no immunity where the germs can spread through the bloodstream and cause meningitis. But it's not only a disease of children. It spreads into young adult life and meningococcal disease, in particular, is well known to continue to be a risk into the 20s and then again in the elderly there are an increasing number of cases, particularly of Pneumococcal meningitis.
PORTER
Last year there were just over 2,100 cases of meningitis in England and Wales. It is a complex condition that can strike at any age. And it has many different causes and outcomes. So to simplify things this programme will be concentrating on bacterial meningitis in children.
Viral forms do exist, but they tend to be milder and self limiting, and rarely require special treatment. Bacterial types on the other hand can be lethal - and none more so than those caused by the meningococcus bacterium.
There are lots of different strains of meningococcus, but it's the Group B type that is the most feared, and the most common.
Like other bacterial causes - such as pneumococcus or haemophilus influenzae (better known as Hib) - meningococcus can present in a number of ways:
It can infect the coverings of the brain causing meningitis; it can infect the blood causing septicaemia without causing meningitis or, if you are really unlucky, it can infect both.
Dr David Inwald is lead clinician on the busy Paediatric Intensive Care Unit at St Mary's.
INWALD
A proportion of children with meningitis will also have features of bloodstream infection, what we in intensive care call sepsis, which means there's bugs circulating in the bloodstream in addition to the localised infection in the lining of the brain. And that's much more dangerous and that's what tends to bring children into the intensive care unit. And there's also a proportion of children that don't have meningitis at all, they don't have an inflammation in the lining of the brain, they just have features of overwhelming bloodstream infection. And those probably account for the majority of our cases.
PORTER
Now the diagnosis, hopefully, has been made or certainly suspected by the time you get them in here, so your first priority is to do what?
INWALD
Our first priority is to stabilise the patient's physiology, by which I mean that we're oxygenating the patient's blood properly, they've got a good blood pressure, there's an adequate blood supply to the brain, that we're maintaining all the organ systems in the body because all of the organ systems in the body can be affected by an overwhelming bloodstream infection, such as we see with this kind of disease.
PORTER
Having the infection in your blood can cause what sort of problems for the patient and you as the doctor looking after them?
INWALD
Well really the kind of things that patients experience are related to both the infection itself but not just the infection it's the body's response to infection, so the body has a profound inflammatory response and that can cause part of the problem. So we know, for example, that far beyond the time when the bugs are all dead and killed, which happens very shortly after the first injection of antibiotics, the body can take many days or even sometimes weeks to recover from the insult that's occurred. So the kind of organ systems that can be affected would include the lungs, we know that the blood vessels can become very leaky, fluid can leak into the lungs, the patients going to need to be on a ventilator, we know that blood vessels can become dilated so the blood pressure can go down, patients often need a lot of fluid. We know that the heart's going to be affected, the heart function can be affected so we often have to give patients high doses of drugs such as adrenaline to maintain the blood pressure and other drugs to maintain blood pressure. We know the kidneys can be affected because the profusion in the kidneys goes down, so patients can sometimes develop renal failure and need to go on to kidney support. And of course they can develop very severe problems with blood clotting and they develop these very characteristic spots on the body and can develop gangrenous areas in the limbs as well.
PORTER
Can you explain what's happening with those spots, I mean this is something that the public are familiar with in pictures, this is the reddish, purplish sort of sports that don't blanch under pressure - so-called tumbler test - but what's actually happening there?
INWALD
Well what's happening is that the endothelium - the lining of the blood vessel - is becoming inflamed and normally the endothelium - the lining of the blood vessel - prevents blood clot formation, it's secretes substances into the bloodstream which prevent the blood from clotting. So the blood will clot in the small blood vessels and in addition to that we know that children who have very severe septicaemia will have a very low platelet count, so the blood clotting is deranged. So as well as having abnormal lining of the blood vessels and being more prone to clot formation in the small blood vessels, they're also more prone to bleeding. So you can get these areas of bleeding under the skin, if you like, and that's why the - when you do a tumbler test they don't blanch, the spots don't blanch, they don't go away because it's the blood cells directly under the skin and you can see them under the glass when you're pressing on the glass.
PORTER
And that same process can actually interrupt the blood supply to the extremities and which is why amputation is a complication.
INWALD
Yes unfortunately it can.
KANE
I rushed to the hospital and on arrival was met by the horrific sight of my son going through what I now know was multi-organ failure. The symptoms didn't all appear in the order that you read about. When I arrived at the hospital the rash was just appearing and it was literally seeing spots appearing in front of your eyes. He had heart failure, they believed that his heart rate for the first three days was 210 beats per minute and the heart was pumping away trying to get the blood to the extremities but the heart couldn't pump the blood down to the extremities and so effectively gangrene sets in and he lost his left leg below the knee, he lost all his fingers on his left hand and he lost most of the fingers on his right hand. So that was the most sort of visible effect of what happened, although while he was lying there they didn't know he had haemorrhaging behind his eyes, he had - they weren't able to tell whether there was brain damage and he had kidney failure, he had - every sort of organ went into meltdown. And so they also treated my daughter, who was just four at the time, and us with some very strong - I believe they were antibiotics. But that was the start of what was then many months in St. Mary's and I believe - certainly at that time - he was the sickest child that they had who survived.
PORTER
The news that a child has been diagnosed with meningitis is bound to trigger anxiety among anyone who has been in contact with them. Particularly as most people think meningitis to be highly contagious. It is not. The risks - even to close contacts - are small, and there are steps doctors can take to minimise them even further. Professor Simon Kroll.
KROLL
There is an increased risk to immediate family members - those who live under the same roof and who have been in very close contact in the time immediately before the infection. And that risk is sufficient that there are protocols and recommendations for a prophylactic treatment to prevent a further infection occurring.
PORTER
So that would mean giving relatives in close contact antibiotics presumably.
KROLL
Antibiotics and where appropriate also making sure that if there's a vaccine available that vaccine has been used and if it hasn't making sure people have access.
PORTER
But the risks are small?
KROLL
The risks are small yes.
PORTER
Generally if a child at a school was to go down with meningococcal septicaemia or meningitis would the other children need to be given antibiotics?
KROLL
I think if this happens it's a very important prompt to deliver a clear and unambiguous public health message and that is to make sure that people are aware of the condition and know what the early signs are and what they should do about it. It's not in itself something which so increases the risk of infection that we recommend a campaign of antibiotic treatment but we do want people to know, if there's been a case, that they should be aware of what the signs and symptoms are so that they can pick up further cases if they should occur.
INWALD
This organism is exquisitely sensitive to antibiotics and early treatment with antibiotics will save lives. We know that mortality in this disease is directly proportional to the number of bugs circulating in the bloodstream. So the sooner we treat these kids with antibiotics the less likely they are to need intensive care and the less likely they are to die.
PORTER
This has been something of a controversial area because my understanding as a GP is that if I suspect someone has this type of serious infection that I should be initiating antibiotics without confirming the diagnosis there in the patient's home, even before ringing for an ambulance.
INWALD
Yes.
PORTER
What's your thinking on that?
INWALD
Well absolutely, I mean that is the recommendation. I think that all of us who work in the field are very clear that early treatment with antibiotics saves lives and that that's the best thing to do, if you're a general practitioner and you suspect the child or even an adult has meningococcal disease in the community and you give them an injection of penicillin out in the community then they're less likely to become so unwell as to need intensive care or indeed to die.
PORTER
But how can we reliably diagnose the condition or differentiate it from other sort of febrile illness, the child might have a bit of flu or a nasty cough or cold? What are the signs that would worry you as a clinician?
INWALD
I think it's very difficult sometimes and I think we have to appreciate in tertiary hospitals like this that it is extremely difficult for people in primary care to differentiate these conditions sometimes. But I guess the kind of things that would make me worry would be a child presenting with signs of early compensated shock. For example a patient has got a very heart rate, the patient is breathing fast, the patient has cold extremities - these all indicate that the heart's struggling to pump blood out to the body. Parents often tell us that their children haven't passed urine very well for the last few hours, again because the kidneys are not perfused so well. They may present with a low conscious level. They may have been off their feeds for a period of time and maybe not so responsive as they normally are. These are the kind of children that really ought to be taken to medical attention as soon as possible, whether that's to the general practitioner or to the nearest accident and emergency department.
PORTER
How quickly after the start of serious infection can it become extremely difficult to treat?
INWALD
Well within hours and it can - and that's one of the reasons why it can be so frightening for parents and is also one of the reasons why it's sometimes not picked up by health professionals because often we hear a story that people have taken their children to the GP or to A&E and been sent home because the child's not that unwell and then six hours later they're at death's door.
PORTER
Dr David Inwald on what signs would worry him. The key thing to remember is that the classic symptoms of meningitis - such as blinding headache, neck stiffness and dislike of bright lights - may not be present at all in children who have only got the bacteria in their blood (those with septicaemia).
Indeed the non blanching rash isn't a symptom of meningitis per se, it's actually caused by bacteria in the bloodstream and so a sign of septicaemia. Either way it's serious.
If you find it confusing - and most people do - there is a full list of the warning signs and symptoms of meningitis and septicaemia in age groups from newborn babies to the elderly - including an explanation of the glass tumbler test - on the Case Notes website at bbc.co.uk/radio4.
But as Dr David Inwald pointed out earlier, making the diagnosis in the early stages can be difficult - even for an experienced doctor. Angela Cloke called her GP when she became concerned about her 18-month-old son Samuel.
CLOKE
He started with a cold and a runny nose, which at 18 months old is nothing unusual. By lunchtime he'd had a sleep, again nothing unusual. So it was only later on in the afternoon when I noticed he had a rash on his legs that in the back of my mind that it began to look a bit suspicious and I began to think this could be meningitis. So I consulted a doctor who actually came out and visited us at home and she checked him very thoroughly but she decided that he had got flu. So she prescribed some antibiotics and reassured me that it was flu and she went away. And so it was only later on that day as the symptoms progressed and I noticed his rash had spread, he'd got a swelling on the side of his foot, blue swelling, that I began to think this just isn't right and I felt quite torn because there's a mother's instinct that nagging away at me saying this isn't right and eventually that nagging doubt became too much and I rang for a second opinion. And a doctor came out to the home straightaway and recognised it as being meningitis the moment he walked through the door because by then his rash had spread so severely. So he was given some injection of antibiotics in the home and taken by ambulance as an emergency to hospital. When we arrived at the hospital it was - it was a little bit like a scene out of a medical drama - we had a team waiting for us as the ambulance arrived and they rushed us in to accident and emergency. He was wired up with heart monitors, temperature, pulse, lots of bloods being taken, intravenous drips into his hand and his foot. As a mum the only bit of him really that I had was his head to stroke his hair and comfort him because he was very distressed. They told me that he was fighting a serious infection, that they thought was meningitis and they would treat it as though it was. They gave him intravenous antibiotics and that was all that they could do, they do that once every 24 hours. And it was literally a waiting game - you sit and you wait and you watch and you watch every breath that they take because this is your precious baby and it's such a serious disease, you know that it is life threatening. He was in hospital for 10 days on intravenous antibiotics and we were very lucky that he pulled through.
PORTER
Samuel was treated at his nearest district general hospital and made a complete recovery, but some children require more specialist care.
The paediatric intensive care unit at St Mary's can cope with the sickest of children, but most hospitals don't have that sort of facility. The Children's Acute Transport Service - or CATS - was set up 15 years ago to provide intensive care to desperately ill children wherever they may be in the North Thames and East Anglia regions.
Concerned doctors can call upon CATS to come and collect ill children - including those with meningitis or septicaemia - and take them to specialist units like Great Ormond St or St Mary's.
Up until CATS was set up in 1992, such transfers were done in normal ambulances, and many children never made it. Today they are picked up by a mobile intensive care unit, manned by specialist staff and the outcomes are very different. Dr Parviz Habibi is reader in intensive care at St Mary's.
HABIBI
CATS will immediately mount a team as quickly as possible and we have certain operational principles and we try and mount a team within 30 minutes.
PORTER
And that team consists of what?
HABIBI
The team consists of a specialist doctor at registrar level - we call them CATS fellows. Obviously the ambulance driver who is a trained paramedic and an intensive care nurse. But all the necessary equipment to deliver airway breathing and circulation support.
PORTER
So they're actually going out in an ambulance or do they use helicopters?
HABIBI
We have a dedicated CATS vehicle, which is an ambulance, which has been modified so that it has essentially mobile intensive care facilities. So everything that you would have in terms of the level of monitoring and therapeutic abilities on the ward on the move.
PORTER
And how effective is that, obviously there must be some compromise to make the unit mobile, is it a dangerous time for the person that's being transferred?
HABIBI
Well obviously transferring a critical ill patient - and this is what they are - can be nothing but hazardous but to make it safe what we need to do is to get there as quickly as possible, the CATS team, on arrival, will do an immediate assessment of the situation, contact their own consultant at the base and say this is the situation, it's much worse than we thought or fortunately it's much better than we thought, they might give another blood transfusion, they might check certain parameters - the child might be going into renal failure, so they might need to stabilise that - just before they make their move and that can take anywhere between an hour and a half to three or four hours.
PORTER
What sort of impact has this sort of transfer had in terms of survival, do we know?
HABIBI
We ourselves published our own data and we found that we had less than 4% transport related adverse events, which ...
PORTER
Compared to - what would it have been under the older system?
HABIBI
About 25% of children had life threatening events and 50% had sort of minor things like - things becoming disconnected but - a near miss event.
PORTER
And you've reduced that now to around 4%, it's a dramatic reduction.
HABIBI
And we'd like it to be zero. So our philosophy has been if you get children with a disease like meningococcal disease refer early and let us together decide, rather than wait until the patient decompensates when it might be too late, I mean you can reach the point of no return in septic shock for example.
PORTER
Can we gestimate the difference in outcomes from managing a very poorly child with meningitis or septicaemia and or septicaemia in a district general hospital compared to the sort of expertise that you might get in a unit that you'd have in a hospital like this?
HABIBI
The major difference comes in multi-organ system failure support, a capability that is the default capability of a tertiary paediatric intensive care unit but is not available in any district general hospital.
PORTER
It would suggest that these children simply wouldn't survive in a district general ...
HABIBI
They would be sent to the adult ITU where such facilities are available for adults but of course the monitoring equipment and the expertise and the staff are not used to dealing with little people especially infants who are tiny and I mean I don't blame them, adult intensive nurses are scared when they see a little child like this because the fluid requirements are totally different, things happen more quickly, everything's miniaturised and really the outcome in adult units, looking after children, isn't as good and that's also been something that's been published as a standard now.
PORTER
Dr Parviz Habibi.
Of course sick children aren't the only people who need looking after. Most parents would agree that there is only one thing worse than being very ill yourself - and that's having a child with a serious illness.
BROADBY
Hi, my name's Sonia Broadby and I'm the modern matron for the paediatric clinical care services at St. Mary's. And I'll just show you our parents' room over here. Here's the parents' room and as you can see it's quite small, so we don't have facilities for people to sleep but we do have basic facilities - tea and coffee making - and we pay for some local hotel rooms so they can stay within a couple of minutes walk away and they've got somewhere comfortable to sleep and we can call them at any time during the night should anything change so that they can come back to the unit.
PORTER
Because presumably when the parents first arrive here I mean they're pretty shell shocked, it's bad enough having your child on ITU for any reason but meningitis must be one of the worst ones.
BROADBY
Yeah it's quite shocking, mainly because it happens so instantaneously. Always a nurse meets the family and brings them in here and explains what we're going to do, whilst we settle the child into the bed space. And then we'll come out and collect the parents and bring them to the bed space and they're welcome to sit there by the bed space 24 hours a day if they wish. We always try and encourage them to go and have a rest at night to keep up their strength and their emotional wellbeing.
PORTER
And is there anything different about dealing with the parents of a child with meningitis compared to your other patients that you have in here?
BROADBY
Sometimes with children with meningitis where they've got severe cases where they might need to have amputations of limbs there's a lot of psychological trauma involved there and so we support those patients with our family liaison nurse and we also have a team of psychologists - a psychology nurse and a consultant - who can come and help us with that if the parents need any extra support.
PORTER
And when the children come on to the ward here do they have to be nursed in isolation?
BROADBY
For the first 24 hours we tend to nurse them in isolation and then they can be nursed in the open ward.
PORTER
Because really it's got quite a lot of variation, I mean some of the children here will be here for quite some time.
BROADBY
Yes some are here for a week, some are here - some can be here for months.
PORTER
And meningitis would presumably be quite a small part of your workload here?
BROADBY
It used to be a very large part of our workload but since the vaccines have come in and they've been quite successful it's now not as big a part of our workload.
PORTER
The introduction of three vaccines against various forms of bacterial meningitis - Hib, meningitis C and, most recently, pneumococcus - has seen the number of cases in England and Wales fall from nearly 3,000 in 1990, to closer to 2,000 last year. But the vaccines can't protect against all types. Professor Simon Kroll.
KROLL
The vaccines to prevent meningitis have been fantastic. Starting with the Hib vaccine, then the meningococcal C vaccine and most recently the pneumococcal vaccine, which has been introduced in the UK. All three of them have really shown themselves to be extremely effective. The Hib vaccine reduced an incidence of cases in England and Wales from above a thousand a year to in the sort of mid 20s and 30s. The meningococcal C vaccine, before the vaccine came in we were looking at nearly a thousand cases a year of that infection, in the last two years we've had 29 and 30 cases respectively, I mean it's phenomenally successful. And the pneumococcal vaccine, which is new to us and we haven't yet got the impressive data, nonetheless there's every reason to suppose that we're going to see a reduction of something like 75% of cases of invasive pneumococcal infection including meningitis and there will be better vaccines to come to bring that number down further.
PORTER
Where are we in developing vaccines for the other strains because once again there's this perception it's a disease that we can immunise against, but of course we can't protect against all, indeed we can't protect against the most feared strain?
KROLL
No that's absolutely right. Meningococcus B is still rightly very much a concern and there are still lots of cases - a thousand cases in England and Wales last year. And there is no vaccine currently to prevent that. But there are some very exciting developments, have been somewhat slow in coming, it's been a very difficult problem, but there are new vaccines based on essentially new technology, different from the meningitis vaccines we have so far, which are in quite advanced stages of clinical trial now against Group B and I think we're looking at times in the next two or three years when we with luck should see these vaccines deployed and we should see the same sort of reduction as we've seen in those other germs that have almost been eradicated.
KANE
The form that he had, which is the B strain, and bacterial form of meningitis there is still no vaccination for it. You pray for all sorts of things and things that are happening and because it happened when he was just nine months old he was learning to walk, so effectively although he was - before it happened - had started cruising around the furniture he then just re-learnt those steps with his new leg. I could cope with the physical impact eventually but I had no idea what the mental scarring was going to be. But he's up at the top of his class and he's adapted unbelievably well, he goes to normal school, he plays in the second hockey team and swims and he does everything that every parent dreams their child would do although in his own way.
PORTER
Most children - and adults - with meningitis and/or septicaemia - will pull through with the right care. Although, like Emma's son Patrick, some may be left with a degree of permanent disability. And even those who appear to emerge unscathed can sometimes develop subtle long term effects like behavioural problems. But caught early, and in the right hands, the outlook is much better than most people think. Dr David Inwald.
INWALD
The vast majority of children who survive intensive care probably come out of intensive care without any long term consequences to their brain function, so often they have normal intelligence. There will be a small number of children who've had a very low blood pressure for a significant period of time and those children may have problems with brain damage and that's often picked up later on. But the majority of children who survive from meningococcal septicaemia, from bloodstream infection, survive without amputations and survive without any brain damage. So it's a very treatable disease.
ENDS
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