In a landmark decision, the USFDA has approved a gene
therapy in the United States. Tisagenlecleucel (marketed by Novartis as
Kymriah) is a therapy for relapsed or refractory B cell leukemia in
children. In this novel therapy, the T cells of the patient are removed
and transported to the manufacturer’s (Novartis) laboratory. Here
genetic manipulation of the T cells is performed to induce the
production of a surface antigen called CAR (chimeric antigen receptor)
in the cells. This receptor recognizes cancerous B cells that bear the
CD19 antigen, and destroys them. The therapy was approved after a phase
II study with 63 patients documented a whopping 83% remission in 3
months.
A dreaded complication (with a black box warning) of
the procedure is the cytokine release syndrome. It is managed with
supportive care, steroids and a specific interleukin-6 blocker –
tociluzimab. Tociluzimab has now received FDA approval for use in
patients on Kymriah who develop this complication. Other adverse effects
of CAR-T cells are B cell aplasia and cerebral edema. Genetically
modified autologous T-cell immunotherapy marks a first step in an
exciting area of therapeutics. It will be closely watched by many. (The
Lancet 9 September 2017)
The Human Dx Project
This project is being touted as the medical
equivalent of Wikipedia. It is an attempt to crowd source medical advice
from experienced physicians around the world along with some tweaking by
artificial intelligence. The basic premise is that diagnosis made purely
by standalone physicians is fraught with significant errors. Artificial
intelligence alone is also not yet the answer to accurate diagnosis. The
Human Dx App can be used by physicians who do not have access to
specialist’s consultations by uploading anonymized patient data,
including history and investigations. Physicians who have enrolled onto
the project will provide free advice. All the various suggestions will
be compiled using artificial intelligence and a single coherent answer
will be attempted.
Ateev Mehrortra and Shantanu Nundy from Harvard
Medical School published a study comparing the accuracy of the Human Dx
to web-based symptom checkers and found that Human Dx clearly
outperformed. Diagnosis by doctors was 84% accurate compared to 51% by
Apps based on symptom-checking. It is conceived that the tool may also
be used by physicians to hone their diagnostic skills. One prominent
challenge involves getting enough physicians to volunteer their time and
free labor to meet the potential rise in demand for remote
consultations. Another possible issue is how its quality control will
address users who consistently deliver wildly incorrect diagnoses. (Scientific
American 11 August 2017)
Cholera Crisis in Yemen
More than half a million people have had cholera in
Yemen since April this year; 2000 have died. More than 25% of the deaths
and 41% of those infected were children.
Two years of conflict between pro-government forces
and rebel Houthi movement has resulted in a ghastly disruption of the
water distribution system and any kind of coherent medical services.
There is extreme shortage of medical supplies, and more than 30000
medical health workers have not been paid for more than a year. War and
conflict take a huge toll in lives and health. The cholera epidemic in
Yemen is a humanitarian crisis of a disease for which both prevention
and treatment exists. (http://www.who.int/mediacentre/news/releases/2017/cholera-yemen-mark/en/)
In the Long Run
An eye-opening commentary in the Lancet begins with the astonishing
feat of a Kenyan who has run a full marathon in 2 hours 25 seconds. The
article discusses possible reasons why East African runners are world
class runners. The WHO recommends that children and adolescents engage
in at least 60 minutes of moderate to vigorous physical activity.
However, in most of the world excluding Africa, inactivity is rampant
starting from very young. 80.3% of children aged between 13 to 16 years
worldwide do not exercise for 60 minutes. The percentage of children who
achieved the recommended 60 min or more each day of physical activity
ranged from 2% in Cyprus to 14·7% in Sweden for girls, and from 9·5% in
Italy to 34·1% in Belgium for boys. In stark contrast, for rural school
children aged 10–17 years from Kenya, moderate physical exercise
durations range 109–193 min per day for girls, and 131–234 min per day
for boys. Not surprisingly, the maximum aerobic capacity levels of these
children are some of the highest. The growing obesity epidemic in India
is a warning that Indian children are going the same way as their
western counterparts. Pediatricians can be champions for encouraging
exercise in children. (The Lancet 12 August 2017).