1 00:00:04,450 --> 00:00:05,290 Sara Dong: Hi everyone. 2 00:00:05,290 --> 00:00:09,670 Welcome to Febrile, a cultured podcast about all things infectious disease. 3 00:00:10,030 --> 00:00:13,660 We use consult questions to dive into ID clinical reasoning, diagnostics, 4 00:00:13,660 --> 00:00:15,040 and antimicrobial management. 5 00:00:15,910 --> 00:00:17,500 I'm Sara Dong, your host. 6 00:00:17,832 --> 00:00:20,322 I'll start by introducing our guests for this episode. 7 00:00:20,742 --> 00:00:23,082 First up is Dr. Veronica Santos. 8 00:00:23,292 --> 00:00:26,831 She completed medical school at the University of Puerto Rico and is currently 9 00:00:26,831 --> 00:00:32,291 a second year in pediatrics residency at University Texas or UT Health Houston. 10 00:00:32,556 --> 00:00:34,026 Veronica Santos: Hi, I am Veronica Santos. 11 00:00:34,360 --> 00:00:37,270 Sara Dong: We have a returning guest, Dr. Misti Ellsworth. 12 00:00:37,280 --> 00:00:41,000 She's an Associate Professor of Pediatric Infectious Diseases at McGovern 13 00:00:41,000 --> 00:00:43,177 Medical School and UT Health Houston. 14 00:00:43,307 --> 00:00:44,747 Misti Ellsworth: Hi, Misti Ellsworth! 15 00:00:44,860 --> 00:00:47,260 Sara Dong: And rounding out the team, we have Dr. Sebastian Shrager. 16 00:00:47,685 --> 00:00:51,885 He completed his pediatric residency at Broward Health in Fort Lauderdale, 17 00:00:51,885 --> 00:00:56,445 Florida before completing a fellowship in Infectious Diseases at the University of 18 00:00:56,445 --> 00:00:58,695 Texas Medical Center in Houston, Texas. 19 00:00:58,875 --> 00:01:02,169 He just started his job as an attending at Wolfson Children's 20 00:01:02,169 --> 00:01:04,059 Hospital in Jacksonville, Florida. 21 00:01:04,275 --> 00:01:05,195 Sebastian Shrager: Hi, I am Sebastian Shrager. 22 00:01:05,923 --> 00:01:08,983 Sara Dong: As everyone's favorite cultured podcast, we like to kick 23 00:01:08,983 --> 00:01:12,823 off the show by asking our guests to talk about a little piece of culture. 24 00:01:12,823 --> 00:01:15,620 Really just something non-work, non-medical related 25 00:01:15,620 --> 00:01:16,970 that brings you happiness. 26 00:01:16,970 --> 00:01:18,700 So, Veronica, maybe I'll start with you. 27 00:01:18,948 --> 00:01:19,548 Veronica Santos: Sure. 28 00:01:19,758 --> 00:01:24,948 Um, I've been reading a book, We Are Liars, which is now a Hulu series. 29 00:01:25,218 --> 00:01:29,333 I've been really enjoying this book and plan on reading the pre sequel after this. 30 00:01:29,830 --> 00:01:30,310 Sara Dong: Very nice. 31 00:01:32,120 --> 00:01:33,080 Sebastian, how about you? 32 00:01:34,415 --> 00:01:38,015 Sebastian Shrager: Yeah, so, uh, I'm, I'm really excited for the World Cup. 33 00:01:38,045 --> 00:01:42,065 It's coming to the United States this summer, and I have, uh, tickets to 34 00:01:42,715 --> 00:01:44,845 Germany-Ecuador, and France-Norway. 35 00:01:45,290 --> 00:01:46,140 I'm super pumped. 36 00:01:46,140 --> 00:01:48,620 I'm a big soccer fan and I can't wait. 37 00:01:49,295 --> 00:01:50,285 Sara Dong: It's so exciting. 38 00:01:50,285 --> 00:01:50,525 Yeah. 39 00:01:50,525 --> 00:01:52,235 It's gonna be, it's gonna be awesome. 40 00:01:52,535 --> 00:01:54,125 Um, and Misti, how about you? 41 00:01:54,981 --> 00:01:58,018 Misti Ellsworth: So I spend most of my free time attending and 42 00:01:58,018 --> 00:02:02,608 embarrassing my tweens and teenagers at sporting events and performances. 43 00:02:03,058 --> 00:02:07,258 When I'm not embarrassing my kids, I like to read and I'm also really 44 00:02:07,258 --> 00:02:10,588 enjoying the, uh, Shrinking series. 45 00:02:10,753 --> 00:02:15,403 Sara Dong: All right, well, today's consult question I have heard is about 46 00:02:15,403 --> 00:02:19,843 ankle pain, so I will hand it over to Veronica to tell us about this patient. 47 00:02:20,868 --> 00:02:21,088 Veronica Santos: Yes. 48 00:02:21,148 --> 00:02:24,673 So to start with, we have a 14-year-old female. 49 00:02:24,673 --> 00:02:28,243 She came in with chronic, intermittent right ankle pain for the past three 50 00:02:28,243 --> 00:02:32,223 years, and she presented with acute worsening over the last 10 days. 51 00:02:32,673 --> 00:02:35,883 Her right ankle pain was intensified during soccer practice. 52 00:02:36,558 --> 00:02:39,318 Three days later, pain worsened and she was now unable to 53 00:02:39,318 --> 00:02:40,458 bear weight on her right foot. 54 00:02:41,248 --> 00:02:44,908 She had two separate visits to urgent care where x-rays were normal and her 55 00:02:44,908 --> 00:02:46,828 pain was attributed to tendonitis. 56 00:02:47,518 --> 00:02:52,168 On day nine, after orthopedics evaluation, MRI of the right foot and labs were done. 57 00:02:53,518 --> 00:02:59,608 On initial exam, her vitals were notable for temperature of 98.2, heart rate of 84, 58 00:03:00,058 --> 00:03:07,018 blood pressure of 115/60, respiratory rate of 15 and saturating at 97% in room air. 59 00:03:08,118 --> 00:03:12,268 On focused physical exam, she had swelling diffusely about the right 60 00:03:12,268 --> 00:03:15,688 heel with tenderness to palpation and a positive squeeze test. 61 00:03:16,348 --> 00:03:20,758 There was no erythema, warmth, or induration noticed and sensation 62 00:03:20,758 --> 00:03:22,348 and active movements were intact. 63 00:03:23,428 --> 00:03:26,728 Her initial labs were significant for a marked increase in inflammatory 64 00:03:26,728 --> 00:03:28,498 markers with no leukocytosis. 65 00:03:29,053 --> 00:03:32,983 Her CRP was 115 and her ESR was 39. 66 00:03:33,643 --> 00:03:38,053 She had slight decrease of hemoglobin to 11.8 with normal platelet count. 67 00:03:39,253 --> 00:03:43,543 Further workup included right ankle MRI, which was remarkable for a 68 00:03:43,543 --> 00:03:49,183 3.8 cm proteinaceous cyst in the calcaneal tuberosity with adjacent 69 00:03:49,183 --> 00:03:52,823 patchy marrow edema and enhancement suggestive of a Brodie's abscess. 70 00:03:53,938 --> 00:03:58,378 The MRI was also notable for edema and enhancement of the quadratus plantae 71 00:03:58,558 --> 00:04:03,428 muscle with a intramuscular fluid collection suggestive of myositis 72 00:04:03,428 --> 00:04:05,648 with possible early polymyositis. 73 00:04:06,668 --> 00:04:09,818 Sebastian, based on this initial presentation, what is your 74 00:04:09,818 --> 00:04:13,423 differential diagnosis so far and would you treat empirically? 75 00:04:14,532 --> 00:04:16,092 Sebastian Shrager: Yeah, so great history. 76 00:04:16,182 --> 00:04:17,852 So Staph aureus is king here. 77 00:04:17,952 --> 00:04:19,992 That's the most common organism by far. 78 00:04:20,502 --> 00:04:24,162 You can also see Group A Strep and Strep pneumo, which still show up. 79 00:04:24,912 --> 00:04:25,882 She's a little too old for Kingella. 80 00:04:27,222 --> 00:04:31,572 Um, so that's lower in the differential and she's not immunocompromised or using 81 00:04:31,572 --> 00:04:33,702 IV drugs, so Pseudomonas is less likely. 82 00:04:34,752 --> 00:04:38,262 And then without sickle cell disease, Salmonella drops way down the list. 83 00:04:38,952 --> 00:04:42,432 That said, Brodie abscesses can be absolutely polymicrobial. 84 00:04:44,322 --> 00:04:48,978 Management wise, this is where people sometimes jump too fast for antibiotics. 85 00:04:49,518 --> 00:04:54,048 If the kid looks stable and not septic, I'd actually hold antibiotics 86 00:04:54,048 --> 00:04:55,628 and call our friends in orthopedics. 87 00:04:56,288 --> 00:05:00,278 Incision and drainage gives you the best chance of finding a bug and holding off 88 00:05:00,458 --> 00:05:02,498 on antibiotics will increase that yield. 89 00:05:02,745 --> 00:05:04,360 Veronica Santos: What if they say no to an I&D (incision & drainage)? 90 00:05:05,002 --> 00:05:05,452 Sebastian Shrager: Yeah. 91 00:05:05,632 --> 00:05:09,862 Um, well, I'll try to persuade them first, but if they still say no, then 92 00:05:09,862 --> 00:05:12,412 cefazolin alone is totally reasonable. 93 00:05:12,502 --> 00:05:18,172 It covers MSSA well and makes oral step down easy to cephalexin, or 94 00:05:18,182 --> 00:05:20,302 cefadroxil, which are great PO options. 95 00:05:21,202 --> 00:05:24,712 If you're living in a MRSA heavy area, then vancomycin makes sense. 96 00:05:24,712 --> 00:05:29,482 And then if you want to also cover gram-negatives and MRSA, you could 97 00:05:29,482 --> 00:05:31,102 do ceftriaxone and vancomycin. 98 00:05:32,734 --> 00:05:34,474 Veronica Santos: Those are all great differentials. 99 00:05:34,714 --> 00:05:38,694 Now how about I give you more history to see if we can add anything else? 100 00:05:39,624 --> 00:05:41,814 She was born term with no complications. 101 00:05:42,174 --> 00:05:46,314 Her only medical history is tendinitis of her right ankle for the past three years. 102 00:05:46,974 --> 00:05:50,424 She has no pertinent surgical history or family history. 103 00:05:50,724 --> 00:05:52,134 Her vaccines are up to date. 104 00:05:52,839 --> 00:05:56,529 She does have pertinent travel history that include a trip to Galveston 105 00:05:56,529 --> 00:06:00,159 Beach in Texas where she stabbed her right ankle on a piece of wood. 106 00:06:00,669 --> 00:06:03,399 The piece of wood was spontaneously expelled from the 107 00:06:03,399 --> 00:06:05,049 puncture site two weeks later. 108 00:06:05,769 --> 00:06:10,119 About five months prior to presentation, she also went swimming in Pensacola 109 00:06:10,119 --> 00:06:13,269 Beach, Florida, and about two and a half months prior, she went 110 00:06:13,269 --> 00:06:15,489 swimming on Canvasback Lake, Texas. 111 00:06:16,329 --> 00:06:19,629 She refers exposure to multiple animals, including ticks, fleas, 112 00:06:19,629 --> 00:06:25,164 mosquitoes, horses, cattle, chickens, possums, iguanas, and even field mice. 113 00:06:25,404 --> 00:06:27,234 And she also has two vaccinated dogs. 114 00:06:28,074 --> 00:06:31,429 How does your differential change now with this additional history, Sebastian? 115 00:06:32,568 --> 00:06:35,538 Sebastian Shrager: So be careful when you go to Galveston Beach, it looks like, 116 00:06:35,538 --> 00:06:36,948 'cause you can get poked with a stick. 117 00:06:37,308 --> 00:06:41,058 Um, now this case gets more interesting because of the water and wood exposure. 118 00:06:41,118 --> 00:06:45,348 Uh, you have to think about Mycobacteria marinum, which loves salt and brackish 119 00:06:45,348 --> 00:06:47,898 waters, and fits a slow indolent course. 120 00:06:48,723 --> 00:06:52,583 The Vibrio species as well, especially vulnificus and alginolyticus, 121 00:06:53,313 --> 00:06:55,938 even though we usually think of them as more aggressive. 122 00:06:56,238 --> 00:07:00,618 She also swam in lakes, so Aeromonas hydrophilia comes into play plus 123 00:07:00,618 --> 00:07:04,338 rapid growing mycobacteria, since they're literally everywhere, 124 00:07:04,938 --> 00:07:06,738 everywhere in all water and soil. 125 00:07:07,578 --> 00:07:12,738 The wood exposure opens the door to fungi like Sporothrix schenckii, probably 126 00:07:12,738 --> 00:07:16,668 lower on the list, but not zero, which really drives home the key point. 127 00:07:16,848 --> 00:07:17,718 Send the bone. 128 00:07:18,348 --> 00:07:23,628 Get aerobic, anaerobic, AFB and fungal cultures because with Brodie's abscesses, 129 00:07:23,688 --> 00:07:28,308 especially with environmental exposure, the diagnosis lives in the microbiology. 130 00:07:28,968 --> 00:07:33,788 I'd also keep a sample on the side to send the PCR testing, just 131 00:07:33,788 --> 00:07:35,108 in case the cultures don't grow. 132 00:07:36,007 --> 00:07:38,047 Veronica Santos: We really do have a broad differential. 133 00:07:38,467 --> 00:07:40,997 I think at this point we're all ready to get some answers. 134 00:07:41,887 --> 00:07:45,217 So our patient underwent two I&Ds by orthopedics. 135 00:07:45,667 --> 00:07:49,057 To our surprise, the pathology and cultures sent from the operating room 136 00:07:49,057 --> 00:07:53,947 revealed Vibrio vulnificus causing acute osteomyelitis, Brodies abscesses, 137 00:07:54,277 --> 00:07:56,647 myositis and bursitis of the right ankle. 138 00:07:57,217 --> 00:08:01,017 The patient was then transitioned from IV vancomycin and piperacillin-tazobactam 139 00:08:01,062 --> 00:08:02,617 to ceftriaxone and doxycycline. 140 00:08:03,487 --> 00:08:06,697 Sebastian, can you talk more on Brodie's abscess, because this 141 00:08:06,697 --> 00:08:10,057 is one of those diagnoses that feel rare and it actually is. 142 00:08:10,677 --> 00:08:11,937 Sebastian Shrager: Yeah, exactly. 143 00:08:11,937 --> 00:08:12,267 Yeah. 144 00:08:12,327 --> 00:08:16,977 So first off, pediatric osteomyelitis overall isn't that common? 145 00:08:17,277 --> 00:08:22,107 It's only about 2 - 20 cases per a hundred thousand kids, and Brodie abscess 146 00:08:22,107 --> 00:08:24,007 makes up only around 2% of those cases. 147 00:08:25,497 --> 00:08:28,647 So you're already dealing with something pretty unusual, and what makes it 148 00:08:28,647 --> 00:08:33,957 tricky is that it's, it's not your classic toxic looking osteomyelitis. 149 00:08:34,467 --> 00:08:39,777 A Brodie abscess is really a subacute form of hematogenous osteomyelitis. 150 00:08:40,047 --> 00:08:44,067 Instead of widespread infection, you get this localized intraosseous abscess, 151 00:08:44,577 --> 00:08:48,747 basically a smoldering infection that the immune system has partially contained. 152 00:08:49,638 --> 00:08:51,108 Veronica Santos: Which makes sense in kids, right? 153 00:08:51,857 --> 00:08:52,587 Sebastian Shrager: Yeah, totally. 154 00:08:52,587 --> 00:08:56,667 So most pediatric osteomyelitis comes from the bloodstream, right? 155 00:08:56,667 --> 00:09:00,207 And the growth plates have this unique vascular anatomy with 156 00:09:00,207 --> 00:09:02,607 slow flow, looping vessels. 157 00:09:03,417 --> 00:09:04,407 Bacteria get in. 158 00:09:05,457 --> 00:09:09,807 The immune system walls it off, and instead of clearing it, you 159 00:09:09,807 --> 00:09:11,087 end up with the Brodie's abscess. 160 00:09:11,982 --> 00:09:15,162 Location wise, Brodie's abscesses love long bones. 161 00:09:15,222 --> 00:09:19,272 Tibia is the big one, about half of the cases, and then the femur. 162 00:09:19,872 --> 00:09:25,002 And interestingly, uh, Brodie abscesses tend to involve the diaphysis more 163 00:09:25,002 --> 00:09:28,692 than the metaphysis, which is a little different from what we usually think 164 00:09:28,692 --> 00:09:30,672 about with acute osteomyelitis in kids. 165 00:09:31,620 --> 00:09:33,400 Veronica Santos: We were all surprised by Vibrio vulnificus 166 00:09:33,700 --> 00:09:35,340 being the causative agent. 167 00:09:35,730 --> 00:09:39,600 Dr. Ellsworth, can you share more on why this was such an unusual case? 168 00:09:40,520 --> 00:09:43,580 Misti Ellsworth: So what made this case really interesting to us is 169 00:09:43,580 --> 00:09:46,220 how completely un-Vibrio it was. 170 00:09:46,730 --> 00:09:50,150 So when we think about Vibrio vulnificus, we usually think about 171 00:09:50,150 --> 00:09:52,400 very dramatic, very fast infections. 172 00:09:52,730 --> 00:09:56,180 So someone cuts their leg in seawater and within days they're septic. 173 00:09:56,180 --> 00:09:59,240 They've got hemorrhagic bullae, necrotizing fasciitis. 174 00:09:59,600 --> 00:10:01,280 Sometimes they end up even in the ICU. 175 00:10:01,970 --> 00:10:05,165 Osteomyelitis just isn't what comes to mind when we think of this bug. 176 00:10:06,035 --> 00:10:08,385 And in fact, when you look at the literature, Vibrio 177 00:10:08,405 --> 00:10:10,715 osteomyelitis is incredibly rare. 178 00:10:11,195 --> 00:10:13,595 Most of what's out there are single case reports. 179 00:10:13,895 --> 00:10:17,315 There aren't any case series and there aren't guidelines talking about it, 180 00:10:17,375 --> 00:10:21,845 and Vibrio doesn't even show up on the usual list of osteomyelitis pathogens. 181 00:10:22,265 --> 00:10:25,025 One of the few detailed reports is from the Journal of Infectious 182 00:10:25,145 --> 00:10:28,625 Diseases in 1990, and that case really mirrors what we saw. 183 00:10:29,765 --> 00:10:34,565 In that report, the patient had a fairly typical exposure, brackish water and a 184 00:10:34,565 --> 00:10:39,335 skin injury, but instead of progressing rapidly, the infection kind of smoldered. 185 00:10:39,785 --> 00:10:42,455 He initially improved with the antibiotics, but over the course 186 00:10:42,455 --> 00:10:46,085 of weeks to months, he developed worsening pain and swelling and 187 00:10:46,085 --> 00:10:48,275 eventually imaging showed osteomyelitis. 188 00:10:48,275 --> 00:10:52,055 The total time course was about 13 weeks, which is just not how 189 00:10:52,055 --> 00:10:53,875 we're taught that Vibrio behaves. 190 00:10:54,640 --> 00:10:56,470 That's what made our patients so challenging. 191 00:10:56,590 --> 00:11:00,460 There was no explosive presentation, no early sepsis, no 192 00:11:00,460 --> 00:11:02,380 necrotizing soft tissue infection. 193 00:11:02,830 --> 00:11:06,520 It said it almost looked like an orthopedic or an inflammatory 194 00:11:06,520 --> 00:11:11,500 condition at first with this chronic pain, local tenderness, no skin 195 00:11:11,500 --> 00:11:14,800 findings, and that really delayed the diagnosis in this patient. 196 00:11:15,685 --> 00:11:19,375 What's striking is that Vibrio infections are usually the opposite of indolent. 197 00:11:19,675 --> 00:11:23,115 Large surveillance studies showed that they present as gastroenteritis, 198 00:11:23,115 --> 00:11:27,195 wound infections, or primary septicemia, not chronic bone disease. 199 00:11:27,585 --> 00:11:32,355 Even during outbreaks, osteomyelitis is almost unheard of, and one Israeli 200 00:11:32,355 --> 00:11:35,835 outbreak with over 60 invasive cases, only one patient developed 201 00:11:35,835 --> 00:11:40,085 osteomyelitis, and there's not a whole lot of details in that case. 202 00:11:41,045 --> 00:11:42,875 So the big takeaway for us was this. 203 00:11:42,935 --> 00:11:46,475 Marine exposure plus persistent focal symptoms should keep 204 00:11:46,485 --> 00:11:49,565 Vibrio on the differential, even if the timeline feels wrong. 205 00:11:50,045 --> 00:11:53,675 Partial treatment, early antibiotics, or lack of source control may 206 00:11:53,675 --> 00:11:57,575 blunt that classic fulminant course and allow a deep infection like 207 00:11:57,575 --> 00:12:00,035 osteomyelitis to slowly declare itself. 208 00:12:01,295 --> 00:12:04,565 And finally, this case is a good reminder that when symptoms don't resolve, 209 00:12:04,595 --> 00:12:08,855 especially pain, repeating imaging and getting deep cultures really matter. 210 00:12:09,185 --> 00:12:13,535 Because even organisms we think of fast and furious can occasionally surprise 211 00:12:13,535 --> 00:12:15,095 us by being slow, quiet, and sneaky. 212 00:12:16,521 --> 00:12:18,621 Veronica Santos: Thankfully despite the chronicity of this 213 00:12:18,621 --> 00:12:22,281 infection and it being Vibrio, our patient had really good outcomes. 214 00:12:22,761 --> 00:12:26,291 On day 15, the second OR culture was positive for Vibrio vulnificus. 215 00:12:26,931 --> 00:12:30,591 On day 16, her inflammatory markers were down trending, and the patient 216 00:12:30,591 --> 00:12:31,506 was doing better clinically. 217 00:12:32,541 --> 00:12:36,201 After completing three days of IV antibiotics, she was sent home with 218 00:12:36,201 --> 00:12:38,481 one month supply of doxycycline. 219 00:12:39,261 --> 00:12:41,781 Patient was followed up in clinic one month after. 220 00:12:42,411 --> 00:12:46,161 At this point, inflammatory markers continue to downtrend with ESR 221 00:12:46,161 --> 00:12:48,321 at 41 and CRP less than three. 222 00:12:48,981 --> 00:12:53,091 The patient completed 12 more days of doxycycline for a total of 42 days. 223 00:12:53,871 --> 00:12:57,501 On day of completion, her ESR level was at 19 and CRP 224 00:12:57,501 --> 00:12:58,881 continued to be less than three. 225 00:12:59,526 --> 00:13:02,556 The patient was later cleared by orthopedics to return to soccer play. 226 00:13:03,846 --> 00:13:08,136 The takeaway from all of this is to think that Brodie's abscess can be subacute, 227 00:13:08,136 --> 00:13:13,326 smoldering, a form of osteomylitis that often lacks systemic toxicity. 228 00:13:13,686 --> 00:13:18,126 When able, as Sebastian said, always send the bone, deep OR culture 229 00:13:18,126 --> 00:13:23,106 should include aerobic, anaerobic, AFB, and fungal cultures, especially 230 00:13:23,106 --> 00:13:24,456 with environmental exposures. 231 00:13:25,296 --> 00:13:29,016 Plus marine exposures and persistent focal pain should always keep 232 00:13:29,016 --> 00:13:32,196 Vibrio on the differential, even when the timeline feels wrong. 233 00:13:34,206 --> 00:13:36,396 Misti Ellsworth: Thanks so much to Veronica, Sebastian, and 234 00:13:36,416 --> 00:13:38,406 Misti for joining Febrile today. 235 00:13:38,916 --> 00:13:42,336 Don't forget to check out the website febrilepodcast.com, where 236 00:13:42,336 --> 00:13:46,086 you'll find the Consult Notes, which are our written show notes for the 237 00:13:46,086 --> 00:13:50,016 episodes with links to references, our library of ID infographics, 238 00:13:50,046 --> 00:13:51,296 and a link to our merch store. 239 00:13:52,066 --> 00:13:55,711 Febrile is produced with support from the Infectious Diseases Society of America. 240 00:13:56,221 --> 00:13:59,251 Please reach out if you have any suggestions for future shows or 241 00:13:59,251 --> 00:14:00,811 wanna be more involved with Febrile. 242 00:14:01,261 --> 00:14:02,041 Thanks for listening. 243 00:14:02,101 --> 00:14:03,901 Stay safe and I'll see you next time.