Day #343 - Interstitial Lung Disease

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Today we presented a challenging case -- where Occam's Razor again met head to head with Hickam's dictum.

The discussant began by talking about the various rheumatoid manifestations in the lung.

We then honed in on interstitial lung disease (previous blog on IPF here), and discussed the phenomenon of acute exacerbation of ILD (other review on non-IPF related AE-ILD here) -- a relatively new concept in respirology.

We also talked about the possibility -- and confirmation -- of pulmonary embolism. Noting of course that PE would not explain the diffuse ground glass opacities.

We discussed the possibility of a superimposed community acquired pneumonia, or TNF-alpha associated granulomatous infection and the need for treatment of same.

Day #341 - Likely TB Pleural Effusion

I missed it today -- but seems eeerily similar to this post....

Day #340 - Occular Myasthenia

Today we discussed a patient who presented with bilateral ptosis. EMG revealed evidence of myasthenia gravis and the patient responded to treatment with an acetylcholine esterase inhibitor.




The JAMA rational clinical exam series addresses the physical diagnosis of MG here.



History:

"speech becoming unintelligible during prolonged speaking" LR 4.5

presence of the peek sign increase the likelihood of myasthenia gravis LR 30 (eyes "peek" open within 30 seconds of closure)

Bedside Tests:

• Ice test LR + 24 LR - 0.16
  (apply ice to the eyelids x 2 mins then evaluate response which should be immediate and short-lived)


• Response to an anticholinesterase medication LR+ 15 LR - 0.11
  (give tensilon, look for response within 30 seconds lasting less than 5 mins)


• Sleep test LR+ 53.0; LR - 0.16
  (have patient lie in a dark room resting the eyes for 30 mins, look for improvement of ptosis)

A review of autoimmune NMJ diseases is available here.

A discussion of myasthenia mimics is available here.

Day #337 - Cirrhosis (PBC)

Today we heard a case of a patient with decompensated cirrhosis (new diagnosis). The precipitant was likely a general anesthetic on the background of unrecognized cirrhosis.

Given the markedly elevated ALP with no bony symptoms and normal ducts on the ultrasound, we proposed a diagnosis of Primary Biliary Cirrhosis (see review here).

See the associated review/editorial on cholestatic liver diseases from a prominant Toronto hepatologist here.

I have also provided a link to a review article on Hepatitis C and HIV co-infection, since it was discussed and is relevant. There is some evidence that HAART may actually worsen the liver disease in these patients and that perhaps the HCV needs to be treated.

Day #336 - Terminal Illeitis and Abscess

Today we heard a case of presumed Crohn's disease (new diagnosis) with intrabdominal abscess. A NEJM review is available here. American practice guidelines are available here.

The NEJM article on the radiation risk of CT scan is available here.

Day # 335 - Severe Influenza

Today we discussed a case that I have talked about before of severe influenza. This case highlights several key issues -- the most important is pointing out just how sick young patients can get with influenza.

We have previously talked about influenza here and pneumonia here.

Day #333 - Hyponatremia

I've previously blogged and referenced hyponatremia here

Day #330 - HSP

Today we heard about a patient with a diagnosis of Henock Schonlein Purpura (Henock left, Schonlein, right). A similar case is presented in the NEJM here.
They presented with a prodromal URTI (more common in patients younger than 30) and then:

• Lower extremity purpuric rash (picture here)
• Abdominal pain with or without gastrointestinal bleeding (GI manefestations reviewed here)
  
• Symetrical arthritis of the large joints in the lower limbs
• Macroscopic hematuria with the development of renal failure and nephrotic syndrome

While mainly a disease of children, approximately 10% of patients with HSP will be diagnosed as adults. In children severe renal disease is rare; however, in up to 30% of adults renal involvement can be severe and up to 10-15% of adults will develop severe renal disease. Treatment in these cases involve steroids with consideration of other immunosuppressants.

Poor prognostic signs include:

• Creatinine more than 120


• Proteinurea more than 1g/day


• Fibrosis or necrosis on kidney biopsy greater then 10%.

The major differential of purpuric skin rash and macroscopic hematuria includes drug-induced hypersensitivity vasculitis, which usually has a good prognosis and cryoglobulenemic vasculitis, which has a much worse prognosis.

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If you speak german, I think this is schonlein's book from 1832 where he first describes this condition.

I've been on a medical history theme this week -- here is an article from 1914 by Osler on HSP.

Day #329 - Fever of Unknown Origin

Today we discussed a patient with fever of unknown origin (previous blogs here including links to the articles I mentioned)

I erred when I said that abdominal imaging was required prior to making the diagnosis -- however, given the ease at which we can get said imaging I would say that it probably *should* be required before labeling as FUO. Certainly, it should be the first test performed in the "second tier"

On the basis of profound inflammatory markers and microscopic hematuria (in the absence of other causes) I postulated that this case may be a medium-small vessel vasculitis such as microscopic polyangiitis. A classic NEJM review on small vessel vasculitis is available here and the corresponding article on medium vessel vasculitis is available here.

This article reviews the guidelines for the management of medium and small vessel vasculitis.

Day #328 Cushing Syndrome

Today we had a patient present with weight gain, facial changes, abdominal obesity, psychosis and hypertension with hypokalemia.

The most common cause of Cushing Syndrome is Cushing's Disease (ACTH producing pituitary adenoma 68%). Ectopic ACTH production and adrenal ademomas are the second most common causes at approx 10% each.

The clinical symptoms and physical signs are wonderfully illustrated in the figure below (with thanks to the TWH CMR who drew it)

The diagnostic algorithm (review here) is as follows:

1. Confirm cortisol excess. 24h urine cortisol or the 1mg overnight dexamethasone supression test are the best in terms of sensitivity and specificity.


2. Is the ACTH high? If yes proceed to evaluate for adrenal adenoma or ectopic ACTH. Is ACTH low? Look at the adrenals.

ACTH High (see original publication by Hurst -- former faculty @ Toronto (memorial tribute here) from 1928 lancet)

From the diagnostic algorithm article: "A woman with mild to moderate hypercortisolism, a normal or slightly elevated plasma ACTH, and normokalemia has at least a 95% likelihood of having Cushing’s disease. In contrast, a patient with prodigious hypercortisolism, hypokalemia, and marked elevations of plasma ACTH may be more likely to have an occult ectopic ACTH-secreting tumor. "

Pituitary MRI is the next step:

Adenoma -- likely not ectopic ACTH (above) = resect

No adenoma, or likely ectopic ACTH = more evaluation

The 8mg dexamethasone suppression test is not sensitive or specific.

Petrosal sinus sampling with CRH stimulation is the best diagnostic test, but is invasive.

If ectopic ACTH confirmed:

bronchial, thymic carcinoids or other neuroendocrine tumors (e.g. islet cell, medullary carcinoma of the thyroid, or pheochromocytoma)

CT thorax and abdomen may find the tumor. If negative consider octreotide scan. Sometimes you won't find it.

Day #327 Anuric Renal Failure

Today we heard a case of a patient post ETOH binging who presented with acute anuric renal failure. We briefly discussed hepatorenal syndrome and then abandoned this diagnosis.

We discussed an approach to renal failure.

We then discussed the possibility of interstitial nephritis, and the role (or lack therof) of testing for urine eosinophils which I have blogged about here.

Some speculations included undiagnosed/untreated pancreatitis or rhabdomyolysis leading to pre-renal azotemia and subsequent acute tubular necrosis (review here).

A nature review of the value of the competant microscopy urinalysis is available here.

Ultimately this patient will have a renal biopsy to make a more definitive diagnosis.

Day #326 Renal Failure and Hemolysis

Today we presented a case of a patient with hepatitis C presenting with a presumed non-antibody mediated hemolytic anemia with renal failure and hematuria.

We have discussed the vascular and renal complications of Hepatitis C, including cryoglobulinemia and membranoproliferative glomerulonephritis previously. Another good review of crytoglobulinemia and hepatitis C is available here.

Note that hemolysis is not a common feature of this syndrome. It is possible that the anemia is related to GI bleeding, particularly small bleeding caused by mesenteric ischemia from vasculitis. Perhaps this isn't hemolysis, particulary because the bilirubin is not elevated (see approach to hemolysis) even though the haptoglobin is low and the LDH is mildly elevated.

This article reviews 'cold hemolytic anemia' or hemolytic anemia related to IgM mediated antibodies and can be seen occasionaly in cryoglobulinemia.