For some years now, we have been hearing about the
Internet of Things (IoT). But it appears that now the Internet of Nano
Things (IoNT) is all set to create a paradigm shift in the practice of
medicine. IoT is a network of ordinary objects including physical
devices, vehicles, buildings and other items – embedded
with electronics, software, sensors, actuators, and network
connectivity that enable these objects to collect and exchange
information. IoT is built from inexpensive microsensors and
microprocessors, and is rapidly expanding the online universe from
computers and mobile gadgets to ordinary pieces of the physical world –
thermostats, cars and door locks. The IoT allows objects to be sensed
and controlled remotely across existing network infrastructure.
These items, especially those monitored and controlled by artificial
intelligence systems, can endow ordinary things with amazing
capabilities. For example, an implanted heart monitor that calls the
doctor if the organ shows signs of failing. It is prophesied that by
2025, the largest percentage of the IoT incomes will go to healthcare.
IoNT goes even further. Scientists have now created
nano sensors which can recognize specific chemical targets at the
cellular level. They can then store and transmit this information to
external sensing device. Their size helps them collate information from
a million different points which can be integrated to generate
incredibly detailed maps. Several classes of medical nanorobots such as
respirocytes, clottocytes, vasculoids, and microbivores have been
designed currently. They could perform a variety of biophysical
clean-up, maintenance, and augmentation functions in the body.
Nanosensors that can detect and quantify biological substances in body
fluids can lead to early detection of cancer cells and environmental
pollutants.
Controversial issues will include privacy, immune
reactions to these nano devices and unwelcome surveillance. But one
awaits the brave new world of computer–human interface with a mixture of
trepidation and awe. (Scientific American 23 June 2016)
Steroids in Tubercular Meningitis
A recent Cochrane review of 9 trials (1337
participants) evaluated the role of steroids in tubercular meningitis.
At follow-up from 3 to 18 months, steroids reduced deaths by almost
one-quarter (RR 0.75, 95% CI 0.65 to 0.87). There was no difference
between groups in the incidence of adverse events, which included
gastrointestinal bleeding, invasive bacterial infections, hyperglycemia
and liver dysfunction. It appears that there might be a slight increase
in disability among participants receiving corticosteroids, but this
increase is counteracted by the beneficial effects on mortality. There
was insufficient data to say whether it benefits patients with HIV.
An article in the Lancet has discussed this review as
well as other interventions which are being considered to reduce
morbidity in tuberculous meningitis. It appears that susceptibility to
immunomodulatory corticosteroid therapy could be genetically determined
by a single nucleotide polymorphism regulating the LTA4H (leukotriene
A4 hydrolase) promoter. There may also be a potential role for anti-VEGF
drugs such as the anti-VEGF antibody bevacizumab and low dose
thalidomide in management of tuberculous meningitis. Low dose
thalidomide has been successfully used to manage selected children with
intractable tuberculomata, persistent optic neuritis, and cerebral
tuberculous abscesses. A study of aspirin in adults found significantly
fewer strokes in patients with tuberculous meningitis receiving aspirin
compared with placebo, but a trial in children produced equivocal
results. (The Lancet 2016; 387;2585-7)
New WHO Guidelines for Multi-drug Resistant
Tuberculosis
Long durations of therapy and poor diagnostic tools
for drug resistance have long bedeviled appropriate therapy in
multi-drug resistant (MDR) tuberculosis. The new WHO guidelines purport
to address these vexing problems. Conventional therapy for MDR TB takes
18-24 months with a paltry 50% response rates. The newer regimen can be
wrapped up in 9-12 months with a substantially reduced total cost of
$1000. The protocol called the Bangladesh regimen is based on studies
involving 1200 patients with uncomplicated MDR-TB in 10 countries. It is
recommended for patients who have not been exposed to second line drugs
like fluoroquinolones or injectables, and are not resistant to them. The
WHO has recommended early diagnosis using the novel diagnostic test –
MTBDRsl. This is a DNA-based test that identifies genetic mutations in
MDR-TB strains, making them resistant to fluoroquinolones and injectable
second-line TB drugs. Test results are available in 24-48 hours a vast
improvement over the currently required 3 months.
The recommendations highlight the advantages of the new regimen (4-6
months of kanamycin acid, moxi-floxacin, protionamide, clofazimine,
pyrazinamide and high-dose isoniazid and ethambutol followed by 5 months
of moxifloxacin, clofazimine, pyrazinamide, and ethambutol). (http://www.who.int/tb/MDRTBguidelines
2016.pdf; The Lancet 18 June 2016).