Indrani Mukerjea is drowsy, consuming liquids and might be back in her barracks by Wednesday. But over the long weekend, the media was yet again thrown into a tizzy by what really caused her to be in a state of “unconsciousness and deep sleep” for over 18 hours.
Two Tests, Different Results
Hinduja Hospital, one of Mumbai’s top NABL accredited private labs found 10 times the normal level of drugs in Indrani’s blood while the state-run, Forensic Science Laboratory (FSL) Kalina, ruled out any possibility of a drug overdose. JJ Hospital, where Indrani was kept, chose to accept the findings of the government-run FSL as authentic and reliable but in a twist treated her according to the findings of Hinduja Hospital. Indrani responded to that treatment as well.
The million dollar question: from the same samples, how can there be two different results? And if there was no overdose, was Indrani naturally unconscious and unable to breathe for almost a day?
Hinduja Test “vs” FSL Kalina Test
To understand the contradictory test results, The Quint spoke to some forensic experts to demystify the drug testing procedure:
1) Any credible drug screening program involves a two-step process. Initial screening or the immunoassay tests (carried out by Hinduja Hospital) and the confirmatory or the Gas Chromatography–Mass Spectrometry (GC-MS) test, (carried out by FSL Kalina). They are both different categories of tests and use different techniques to establish results.
2) Immunoassays are simple, basic tests which give “false positive” results many times, therefore, every positive result is typically sent for the more advanced, more superior, more accurate confirmatory or the GC-MS test.
3) Perhaps this explains why the FSL laboratory at Kalina also got a drug overdose “positive” in the first two rounds of the same screening tests as Hinduja Hospital.
4) Confirmatory tests are used for a more detailed analysis; to identify the exact drug which was abused, to confirm a positive and sometimes negative test results.
5) By the law: unless a combination of both tests give a positive, the results are not accepted as positive. The results of the confirmatory tests are deemed final and authentic since they are far more sensitive and specific.
Possible Causes For False Results
1) Cross-reactivity, a big limitation of the immunoassay tests: If we assume Indrani overdosed on drug X, then the other medications she was on, even vitamins, can interfere with the initial screening tests to give a false result.
2) Deliberate adulteration of the urine samples by the subject. If one purposely drinks excessive water before giving the urine samples for final testing, the level of drugs will definitely be watered down. This seems difficult because Indrani was wheeled in an unconscious state to JJ Hospital.
3) Tampering of the samples at the laboratory. Certain enzymes can be added to affect the stability of the sample and thereby give a false negative result.
Perhaps this explains the ‘overdose to no overdose’ stance of Dr TP Lahane, Dean of the Sir JJ Group of Hospitals. His explanation has been:
They are not different results but different tests, hence the diverse results. Hinduja labs have done the immunoassay tests which are preliminary tests to help a doctor treat the patient. FSL Kalina did three rounds of tests, the first two immunoassay tests done by them also show an overdose.
–Dr TP Lahane, Dean, Sir JJ Group of Hospitals
It is not the protocol to send urine samples to two hospitals but Dr Lahane insists that this was done because private laboratories send reports faster and it helps doctors decide on the treatment angle. Hinduja Hospital has an NABL accredited lab and samples are often sent to them for clinical examination in many medico-legal cases.
So if there was no drug overdose, what could’ve caused “respiratory distress” to Indrani which knocked her unconscious for almost a day?
Medically: any chronic lung disorder, blood infection like sepsis, swine flu, pneumonia, an injury to the chest or head and inhaling toxic fumes can induce respiratory distress.
Logically: the entire chain of events and the clinical reports are as bizarre as the case itself. It’s a waiting game to see what the former media mogul says in her statement to the police.
(At The Quint, we are answerable only to our audience. Play an active role in shaping our journalism by becoming a member. Because the truth is worth it.)