Osteomyelitis in children/ Bone infection in children

0:00 hi this is Omar abdad and we're going to speak about bone infection or what's known as osteitis in children so what are objectives of this lecture first would like to describe the pathology of osteitis and then we would like to describe what are the pathogens that cause osteitis and explain the clinical presentation of this disease also would like to treat the treatment of osteitis and a very important we'd like to compare between acute and chronic osteitis in pathology clinical presentation and treatment a good source that you can use to read more about this topic is pediatric orthopedic a handbook for primary care physician uh this book is written by myself and Dr Naga so let's starts with acute hematogenous osteitis this is the most common form of osteitis in children what is the

0:47 definition of this condition is an acute infection of the bone and the bone marrow so acute hematogenous osteitis is an acute infection of the bone and more marrow it's more common in boys between the age of 4 to 6 years let's discuss now the pathology of acute hematogenous osteitis it happens in in the metaphysis first what is the metaphysis metaphysis is the area of the bone which is close to the fisis so this is the growth plate or the fisis this is the epiphysis and this is the metaphysis metaphysis is the area of the bone which is adjacent to the fisis and why it affects the metaphysis affects the metaphysis mainly because of its slugish blood flow so the blood goes here from the aant arules becomes very slugged and slow here and then it comes back with

1:34 the Venus sinusoids that's why it mainly affect the metaphysis so what exactly happens so bacteria from distant Focus like infection in a skin or a teeth or a nose comes through the blood and then because of the slow slow and sluggish blood flow here in the metaphysis it settles here and forms the infection that's why we call this type of osteitis hematogenous osteitis because it spreads um by bacteria From A Distant Focus so it spreads with the from the blood and the bacteria from distant Focus comes and settles here because of the sluggish blood supply in this area so what's happen after the bacteria settled in in the metaphysis so the bacteria will come from a dist Focus as we said settle in in the metaphysis here form a focus of infection it will be

2:21 surrounded by inflammatory cells and then it will end having a metaphys absis here in this area so this is the pathology of the osteitis as we said its bacteria comes from a distant Focus settle into the metaphysis by its slow blood supply and sluggish circulation and then it will form a focus of infection inflammatory cells will come and then it will end having metaph physial absis after we had discussed the pathology of ositis let's speak about the microbiology so sta orus this is the most common pathogen in all age group and be aware of the strings of the staff orus which are um methylin resistance so M MSA is a common cause of osteitis in children in in all age groups uh certain

3:09 other bacterias also are common in certain population like Group B stripto cocas and eoli they are common causes of osteitis in the Nate causing Neal osteitis so if you have a kid you're suspecting Neal osteitis group b streptococus or e coli are common pathogens also salmonella is a common pathogen in cases of children with CLE cell anemia and STP pneumonia is a common cause of osteitis in children less than 24 months of age recently uh there is an organism called kangela kingi and it has been found to be a common cause of muscular scal infection both arthritis and osteitis the problem is identification of Kanga kingi needs certain cultures however now after the

3:55 use of uh PCR polymerase Chain Reaction um identification of this organism is um more common and there has been some studies that shows Kila kingi may be actually one of the commonest organism to cause osteitis and arthritis what about the clinical presentation of osteitis so first the child will present with the general size of infection which is fever vomiting uh ill looking toxemia chills and also you can find the local manifestations of the infection on the affected bone so you'll see redness hotness tenderness and swelling this is more easily detected with bones which are subcutaneous like the proximal tibia or the distal fibula and if ositis affects bones of

4:43 the lower extremity this would be accommodated with inability to wear bait on the affected side so in case of osteomylitis you will find elevated markers of infection however this may take few days to show up so you'll find elevated white blood cell count elevated cedrate and elevated C reactive protein let's speak now about the Imaging studies for patients with osteitis the first thing that you have to get is a radiograph plain x-ray this is very important so you start with the x-rays because it's very helpful to exclude other causes um of pain and swelling like fractures or tumors uh keep in mind that the x-rays will be negative for the first 10 to 14 days of the disease process so if you have a patient with osteitis um that the condition started

5:28 only four or five days ago when you get the X-ray the X-ray may be completely negative after 10 to 14 days you'll start seeing proster reaction as you can see in this case this is a toddler with upper tibial redness and swelling for more than 10 days and if you look closely here you can see the perio reaction here and the perio reaction here so this is uh the boundary of the bone here and if you look very closely you'll see the periost reactions where the tip of the arrow is is um so after 10 to 14 days you can start seeing prosto reaction as an indication of an infection in case of chronic osteitis as we're going to see later there are specific changes that happens in the x-rays and we were going to discuss that

6:14 later in the lecture uh bone scan this is a very useful Imaging tool to detect infection and we order the triphasic bone scan this is the bone scan that we order if you're suspecting an osteitis and basically the triphasic bone scan it measures the blood flow to your bone in three different um uh time periods and in cases of infection you will it will appear as a hot spot of the infection side if you can see this is a CH a child with a suspected infection bone scan was taken and if you compare the right to the left side it's obviously has an increase uptake or what we called Hot Spot in the upper right tibia indicating osteomylitis let's speak now about MRI

7:00 MRI use for to diagnose osteitis has been increasing recently and to a large degree it has replaced the use of the triphasic bone scan so the MRI is very sensitive to diagnose osteitis and and how it will show in osteitis it will show as um increased signal on T2 weighted images and there will be enhancement of the medala of the affected side uh so if you see this is an MRI of a child who presented with lower leg pain um and inability to put weight the MRI show very clearly that this child has an increased um signal in the t2 weighted images in the lower tbia which is very consistent with having an osteitis um what is the

7:46 advantage of the MRI MRI has some advantages in case of osteitis first it become very posit it becomes positive very early in the disease process so you don't have to wait for 10 to 14 days as in plain radiogram and also it can show the sub periostal absis the sub periostal absis is when the exudate collects underneath the prosum and we this and as we're going to see later on this is an indication for surgical intervention so you can see this in the MRI another advantage of the MRI it can show if there is an affection of the nearby joint indicating possible combined osteitis and septic arthritis this happens sometimes in the hip joint in which the upper uh part of the femur is in the capsule and cases of osteitis

8:34 can spread to the Joint causing septic arthritis so MRI now is becoming the standard of diagnosis for cases of osteitis it's very sensitive it can show the area of affection very clearly it becomes positive in very early in the disease process it can show the subio absis and it can show combined cases of ositis and septic arthritis so what are the condition patient that can present similar to oitis we have a saroma sometimes present similar to oitis the kid will present with pain and swelling of the affected extremity he will have elevated markers of infection so he can have elevated ESR or C active protein however radioraps will help you differentiate between ositis and awing saroma in case of awing saroma you will

9:19 find bone destruction um elevated uh periostal and new periostal bone formation and remember that aing saroma affects mainly the diaphysis of the bone rather than the metaphysis in cases of osteitis septic arthritis also sometimes present very similar to um ositis sometimes the differentiation between septic arthritis and oitis is very hard however if you examine the child closely you will find that most of the pain is related to The Joint and the joint movement so if you try for example to move the knee and the child has Osteo has septic arthritis any passive movement of the knee will cause severe pain to the child you will find that the child um is really preventing any movement of the affected extremity uh MRI will help you to differentiate between septic arthritis

10:06 and oitis however keep in mind that septic arthritis and oitis sometimes happen simultaneously together especially in the hip and the shoulder in which there is communication between the proximal femur and the hip and the proximal humoris and the shoulder joint after we had discussed the diagnosis of osteitis let's speak now about treatment of osteitis the fact that I'd like to stress here is osteitis is a medical condition so oitis is a basically a medical condition that in certain circumstances it needs some surgical intervention however it remains a medical condition that can be totally treated with antibiotic this is a very important fact that I'd like to stress an osteitis is a medical condition it can be treated with antibiotic alone however there are some certain indications for surgical

10:53 intervention that we're going to see later on so you have to give that antibiotic in the appropriate um do and for the appropriate period of time and this antibiotic of course has to be the correct antibiotic for the offending organism that's why obtaining culture is very important for the treatment of osteitis and you have to obtain cultures from the affected side and you can do that or you can refer the patient to the intervention radiologist and then you introduce a 16 gauge needle and aspirate from the bone marrow so that you can get some um specimen for the cultures and be able to know the offending organism after we knew that antibiotics is the main treatment of ositis let's discuss now um the different aspects of the

11:39 antibiotic so the antibiotic in general has to be the organism sensitive antibiotic for a total of six weeks so this is the general rule it's the organism sensitive antibiotic for a total of about 6 weeks how do we know the organism this is by culture as we said before blood cultures or cultures uh from the affected um area if you don't have positive cultures you can depend on the knowledge of the most prevalent bacteria in the patients age group and in the ancient geographic area which he comes from uh usually we give two weeks of Parental antibiotic followed by four weeks of oral antibiotic this is the general rule however this um changes according to the um organisms and if there is available organism sensitive antibiotic oral or

12:25 not so if you have a good oral antibiotic that is sensitive to this bacteria you can go less with the parental antibiotic and go longer with the oral antibiotic if you don't have any good oral antibiotic that's going to um be against that specific bacteria you can go the whole period with parental antibiotic in this case um you have to get a peripheral line or what's called pick line so that the patient can have the antibiotics through that pick line uh what is the antibiotic that we start we start usually with IV clinty or another broad spectrum antibiotic till we have the results of the cultures and the sensitivity uh if you live in an area that is more prevalent with methylin resistance St oras you can start with Vancomycin till you get the

13:11 cultures and you always have to monitor the response of the patient clinically if you give the antibiotic the patient should within 36 hours have marked improvement also uh the C Ser active protein will show Improvement the values will become less ESR will take a long longer time to come to normal sometimes it WS it takes weeks so we don't depend on the ESR usually we depend on clinically fever and pain um and on this C reactive protein to monitor the response of the patient to the treatment after we spoke about the antibiotic treatment for osteitis which as we said is the main State treatment for osteitis let speak about the indications for surgical interference what are the reason that will make you call the orthopedic surgeon to come to do surgery

13:58 for these kids there are three main indications for um surgical intervention in case of osteitis which is the development of subperiosteal absis as we as mentioned in the MRI uh so if you get an MRI for this patient and there is collection underneath the prosum this collection has to be drained um the second indication if there is no response to the medical treatment after 36 hours so you give the antibiotic uh parthal in the beginning and there is no response after 36 hours the patient still have fever and pain this is indication for surgical intervention also if there is an extension of a nearby Giant so a proximal femur osteitis extended to the hip and that became a septic arthritis of course now you have to op because septic arthritis is a surgical condition so there are three main indications for surgical

14:45 intervention in case of osteitis um sub number one is sub oal absis number two is no response to medical treatment after 36 hours and number three is extension to nearby joint so again very important please remember that osteitis is a medical disease so it can be treated completely by antibiotic there are certain indications that will make you uh refer this patient to an orthopedic surgeon or ask for an urgent Orthopedic consult um and these are the subperiostal absis no response to medical treatment after 36 hours or extension to nearby joint after we had discussed acute hematogenous osteitis which is the most common form of osteitis in children let's speak about the non- hematogenous osteitis so what what are the causes of the non- hematogenous osteitis in

15:31 children it can be post trumatic osteitis so it can happens after open fracture there is a fracture with a connection between the fracture and the external environment that can get infected and can cause osteitis penetrating trauma also if they reach to the Bone can cause osteitis puncture wounds if they are deep enough they can cause osteitis postsurgical which means after an orthopedic surgery patient develop infection which extend to the bone that can cause also osteitis human and animal bies if they are deep enough they can cause osteitis the cubitus ulcers in children who are not ulating it can extend to their sacrum and cause osteitis and it can be also local spread of infection for example in growing toenail can cause osteitis of the FES of the toes these are all causes for non-

16:18 hematogenous osteitis the management of non hematogenous osteitis is basically antibiotic which is similar to the hematogenous osteitis however most cases of non penous osteitis will require Orthopedic consultation as most of them will require surgical DE bment after we have discussed acute ositis let's speak about chronic osteitis so what is chronic osteitis chronic osteitis is an osteitis with chronic changes of the affected bone so if the acute osteitis was not completely cleared and chronic changes happens in the bone we call this chronic osteomyelitis uh what is the pathology in case of chronic osteomyelitis there is two main things in chronic oitis sequestrum and involucrum sequestrum is when there is a dead piece of the bone

17:05 that become separated from all the surrounding tissues this um piece of the bone will become more dense in the X-ray so if you see this piece here and this piece here uh this is a sequestrum it's part of the bone that become separated from all the surrounding tissues by the infection and these parts became Dead uh this is these pieces um here you can see them after excision of this uh sequestrum uh surgically involucrum involucrum is a periostal new bone formation so if you see in this picture you see all this is a periostal new bone formation all this is a periostal new bone formation and this is a repeative process of the bone to try to strengthen the bone structure so chronic oitis it is Otis with chronic changes so if acute osteitis is not cleared completely it

17:52 will lead to Chronic oitis of the bone the two main pathology um to uh know are is the sequestrum and the involucrum the sequestrum is a dead piece of bone in most cases it appear in the X-ray as more dense structure as you can see in this part and this part and involucrum is the preal newone formation as you can see here it's a reparative process that the bone is trying to strengthen the bone structure this is another x-ray of a six-year-old girl with chronic osteitis if you can see here the invol uh this all this is a pral new bone formation uh that is a sign of chronic osteitis management of chronic osteitis required Orthopedic consultation so if

18:37 you remember when we discussed before we said acute osteitis is a medical condition however chronic osteitis cannot be cured medically so this has to be referred to an orthopedic surgeon and if there is sequestrum this sequestrum has to be removed surgically as we saw before um because um otherwise there will be recurrent infection from these septic Focus antibiotic treatment in general you don't need antibiotic for chronic asitis except if there is an acute exacerbation of infection so if you see a patient presenting with a new onset of local pain swelling or fever on top of a chronic emitis you can give an antibiotic therapy or after surgical interference to clear the infection thank you very much