Leptospira

00:01 Leptospira, a bacteria.

00:03 The leptospira are the smallest of the spirochetes.

00:07 They are aerobic organisms that have hooked endings which actually help them with their adherence factors.

00:13 Leptospira interrogans is the only species we know of that is pathogenic in humans.

00:20 In the picture on the slide, you can see evidence of these smallest of spirochetes, it doesn’t even look all that spiral in nature only because it’s so very small and so very hard to see the variations in the typical screw like or spiral form.

00:36 Who transmits Leptospira? These lovely and adorable animals in slide two - rodents, pet rodents, wild rodents, household pets such as that poor sad looking dog waiting for his owner to come home - are all very nasty in that they shed leptospires via the urine and sometimes, they contaminate the water supply.

00:59 In fact, most transmission of leptospira occurs through contaminated water which has been contaminated by animals, most often though, wild animals not our lovely pets at home.

01:12 Let’s look now at the clinical diseases associated with infection by Leptospira interrogans.

01:18 The disease is leptospirosis, although it occurs in two forms, regular leptospirosis and then a very severe form called Weil syndrome, icterohemorrhagic leptospirosis.

01:28 and then a very severe form called Weil or Veil syndrome, icterohemorrhagic leptospirosis.

01:32 The Weil syndrome is when an exaggerated immune reaction has occurred to a leptospira within organ systems. and even within the blood products.

01:40 Presentation for these two initially starts as a mild flu-like illness, low grade fevers, myalgias, malaise, but in the Weil syndrome it can be associated with shock, hypotension, and multi-organ dysfunction.

01:56 Patients who are most at risk for leptospirosis are those who are out experiencing the outside world and all of its many wonders.

02:04 Surfers, mostly because they are exposed to water which may be contaminated by animal urine in fresh water creeks and rivers emptying into the tropical oceans, also, too, are those who experience the outside adventure sports such as triathletes or those in like the Borneo high adventure races where they are running and then sometimes swimming through contaminated fresh waters.

02:31 Of the patients with leptospirosis, approximately 10% will develop the more severe form potentially because they have been prior or previously immunized or not to say vaccinated but exposed to leptospira and they have already a pre-prepared immunologic reaction or they may genetically just be at risk for a much more robust reaction.

02:57 Signs and symptoms of regular leptospirosis.

03:00 Again, flu-like - think relatively nonspecific - so myalgias, classically of the lower extremities and of the calves which by the way, for those runners and triathletes out there, is a very common finding even after a training event so it may be mistaken for simple heat exhaustion and overdoing it in running the race.

03:22 Patients with leptospirosis may also have a non-specific erythematous maculopapular rash which is very mild in fact it may look a little bit like a blotchy rash associated with heat stroke.

03:36 They may also have photophobia, be sensitive to the bright lights and to the sun along with conjunctival suffusion which would be like conjunctivitis but without any sort of a watery or purulent exudate.

03:49 In contrast, the patients with Weil syndrome start with the flu-like illness and then rapidly develop severe headache and then findings of end organ dysfunction or multi-organ dysfunction.

04:01 Jaundice because the liver has shut down, azotemia because the kidneys have shut down.

04:08 Hemorrhages, vascular collapse because of this effect on endovascular or blood vessel lining stability and then because of that they’re anemic in part due to blood loss and in part due to a hemolytic process.

04:25 Again, patients with Weil syndrome are very, very sick.

04:29 Testing for Leptospira can be done via an ECG ELISA on serum or via PCR using either serum or urine.

04:36 These tests typically take three to up to ten days to complete, so it is important to remember that if there is high clinical suspicion, treatment should be initiated prior to the test results being available in the States.

04:50 If the test is confirmed, samples should be sent to the Centers for Disease Control for zero. Var determination as leptospira is a notifiable disease.

04:58 Treatment for either typically could be penicillin or a macrolide such as erythromycin.

05:04 Doxycycline will also work, again, if somebody is treating empirically not knowing what the exposure may have been, then doxycycline is the reasonable choice.

05:14 But, if one is very suspicious of or has confirmed the diagnosis of infection with leptospira interrogans, then penicillin is the drug of choice.

05:24 So this is one of those infections that thankfully occurs somewhat rarely but infection with leptospira can typically be tracked to environmental exposure, some sort of exposure to fresh water which may have been contaminated by animal urine and the onset of a flu-like illness followed in severe cases by Weil syndrome with multi-organ dysfunction.

05:43 and the onset of a flu followed in severe cases by Weil syndrome with multi-organ dysfunction.

05:47 Leptospirosis, definitely a traveler’s nightmare.