Paraphimosis and Phimosis

What is it?

Paraphimosis: the penile foreskin becomes retracted around the coronal sulcus (= the circumference at the base of the glans penis), leading to vascular congestion and glans edema

Phimosis: the foreskin is retracted over the glans

This is only an emergency if it is causing acute urinary retentionKeep in mind most uncircumcised infants have normal phimosis

Why do we care?

 If left untreated, paraphimosis can lead to some awful complications, such as necrosis or gangrene of the glans penis which can then necessitate a partial amputation of the penis 

For phimosis causing urinary retention, can cause infections and renal failure

When to suspect it?

The main risk factor is lack of circumcision.

Crying infants (the S=Strangulation in ITCRIES for those who love mnemonics)

Adolescents may present later due to embarassment - can be caused by genital piercings or sexual intercourse 

Another risk factor is prolonged erotic dancing, ie wining - a gyrating motion that alongside others causes prolonged erection and friction on the penis (multiple case reports)

How do we manage it? 

Don't miss other injuries - look at their scrotum for a concomitant torsion or Fournier's 

Paraphimosis

Call urology urgently if you note signs of ischemia or the patient has had symptoms for >12 hours.

If there are no signs of ischemia, consider non-manipulative methods, which entail a combination of compression and osmotic agents as well as patience:

1. "Iced Glove" - place ice and water in a glove and invaginate the thumb portion to place the penis into

2. Mannitol or glucose soaked gauze - soak gauze in 20% mannitol or D50 and wrap it around the glans of the penis while applying gentle pressure; this can take 1-2 hours for full effect

Next, attempt manual reduction. Don't forget pain control!

Methods of analgesia: topical EMLA, dorsal penile nerve block, fentanyl, ketamine, procedural sedation (though certain studies have shown topical anesthesia may work best) 

Manual reduction: Have both thumbs on the glans while applying countertraction with the index fingers to the foreskin

If it works, make sure the patient can freely urinate , instruct patients to not retract the foreskin for 2 weeks, and arrange urology followup in 2-3 weeks. 

If it fails, URGENT urology consultation. There are other options in case of a failed manual reduction (injecting hyaluronidase, aspirating the glans, poking the foreskin) that are especially useful if no one is immediately available to assist you 

Phimosis

If causing acute urinary retention, call urology for likely dorsal slit procedure.

If patient is able to freely urinate, educate patient on how to properly clean their foreskin and show them how to retract the foreskin (3 months of this exercise has been shown to lead to resolution of phimosis in 76% of patients).

Topical steroids (triamcinolone for 4-6 weeks) also improve or completely resolve phimosis.

Sources

http://www.emdocs.net/em3am-paraphimosis-and-phimosis/

https://pedemmorsels.com/pediatric-paraphimosis/

https://www.aliem.com/trick-trade-management-paraphimosis/

Contrast induced nephropathy

Dear pearl of the day readers,

I suppose you could consider this is a part 2 on side effects/toxicity of Iohexol (omnipaque™). This pearl of the day comes at the personal request by one of my coresidents to cover this topic.

Epidemiology

Contrast induced nephropathy (CIN) is an increase in serum creatinine > 25% after administration of IV contrast.

2-10% of patients who received iodinated contrast media suffer acute kidney injury (AKI). The peak of AKI is seen 2-3 days later.

A caveat here is that many times patients will develop AKI from other etiologies after receiving contrast. This makes sense because they needed a CT scan for some clinical indication.

Patients who have pre-existing renal disease or elevated serum Cr are at higher risk for CIN. There are scoring models to see who is at higher risk, but this applies more to interventional procedures requiring higher contrast loads. If you are curious about the scoring systems they can be found here: http://www.kdigo.org/clinical_practice_guidelines/pdf/KDIGO%20AKI%20Guideline.pdf

Side note I found interesting: in patients who had no protein in the urine, only 1% had a Cr>1.7 mg/dL. So no protein in the urine means they probably do not have kidney disease.

Mechanism

The putative mechanism of injury to the kidneys is renal vasoconstriction and direct toxicity to the renal tubular cells, possibly through increased reactive oxygen species.

Chance of recovery

Patients who develop CIN have higher odds of mortality, 1.9. If the CIN requires dialysis, in hospital mortality at one institution increased from 7.1% to 35%.

One British study found that 0.9% of patients developed CKD within 6 months of receiving a contrast loads, compared to 0.17% of patients who developed CKD during the same time period.

So the chances are good the patient will recover.

Treatment

There is no proven treatment; however, pre-treatment with IV or PO fluids is the mainstay practice. In the sense that dehydration is bad for the kidneys, it is reasonable to try to avoid a second hit. However, conflicting data show that there was no difference between fluid pretreatment or not.

Several controversial studies may show that pretreatment with sodium bicarbonate was superior when compared to normal saline (NNT=10); theoretically, this effect is due to decreased free radical formation.

Also theoretically, N-acetyl cysteine (NAC) can help reduce oxidative stress on renal tubular cells. The official journal of the international society of nephrology actually recommends pretreatment in patients at increased risk for CIN with ORAL NAC. High dose oral NAC was shown to decrease the incidence of CIN by 76% in one study. Data is also conflicting here, but trends toward favoring the use of oral NAC in patients at risk for CIN.

Lastly, preliminary data also shows that statins may some how be protective through an unknown mechanism.

Final take home points

Be cautious:

-if the patient is on other nephrotoxic agents

-if the patient has a slightly elevated creatinine compared to baseline (even if it still normal)

-if there is protein in the urine

-if they have a history renal disease

-if eGFR<60

Balance the risk of contrast against the risk of not-performing the correct radiology study. This will be different for every patient.

TR,

W

References

http://www.kdigo.org/clinical_practice_guidelines/pdf/KDIGO%20AKI%20Guideline.pdf

Merten GJ, Burgess WP, Gray LV, et al. Prevention of contrast-induced nephropathy with sodium bicarbonate: a randomized controlled trial. JAMA. 2004;291(19):2328-34.

Patschan D, Buschmann I, Ritter O. Contrast-Induced Nephropathy: Update on the Use of Crystalloids and Pharmacological Measures. Int J Nephrol. 2018;2018:5727309.

Reuben Strayer's response to my post is quite poignant and definitely worth a read:

Despite how penetrated the notion of CIN is in our teaching and practice, and how much time and energy we spend on its supposed prevention, there is considerable controversy as to whether CIN actually exists/occurs.

paper

audiocast

Farkas’ blog post

Morgenstern's blog post

I’ve pasted conclusions from the latter below. The most important point is if you have a high concern about a dangerous condition and require an IV contrast-enhanced CT scan to rule it in/out, the patient’s creatinine should factor minimally if at all in your decision around whether or not to do the scan. Do the scan.

It is not clear whether contrast is a significant cause of acute kidney injury. According the the American College of Radiologist, “at the current time, there is very little evidence that IV iodinated contrast material is an independent risk factor for AKI in patients with eGFR ≥30 mL / min/1.73m2”. (ACR manual 2017)

We need some large RCTs to settle this issue. There is clearly equipoise on this issue and there should be no barriers to running a RCT.

We should stop using the term “CIN or contrast induced nephropathy” as it implies a degree of causation that simply is not supported by the literature. Post contrast acute kidney injury more appropriately describes what is occurring.

If a patient needs contrast to make an important diagnosis and there isn’t an easily available alternative test, just do the scan. Even if contrast causes acute kidney injury, true patient oriented harms are only seen in a very small number of patients. There is a balance, but as long as the pretest probability of important pathology is higher than the chance of harm (probably less than 1%), the patient will still benefit from the contrast CT.

Nephrotic Syndrome Pearl of the Day

Nephrotic Syndrome

Pathophysiology

Think about it like this: Glomerular basement membrane problem, you spill all your protein (albumin) from your plasma into your urine, leading to high urine protein, low serum protein, and edema. It may help to simply think of it as decreased oncotic pressure causing movement of fluid from the intravascular space to the interstitial space; in reality the pathophysiology of edema in nephrotic syndrome is a little more complicated - has to do with a combination of primary (due to renal disease) and secondary (via RAS pathway) sodium retention.

Thus,

nephrotic syndrome is defined by:

1. Heavy proteinuria

(protein excretion > 3.5 g/24 hours; UPEE>3.5; >2 in children)

2. Hypoalbuminemia

(< 3 g/dL; <2.5 in children)

3. Peripheral edema

(Hyperlipidemia and thrombotic disease are frequently observed with nephrotic syndrome but not required for the diagnosis, may also be immunosuppressed)

(UA should have no significant hematuria, casts, or RBCs which would suggest a nephritic picture)

Measuring Proteinuria 

The most convenient way is to calculate a 

Urinary Protein Excretion Estimation (UPEE)

(insert infantile bathroom humor here)

UPEE (g/day) = (urine protein (mg/dL)) / (urine creatinine (mg/dL))

This works because a random urine protein to urine creatinine ratio very closely approximates the true 24 hour urine protein excretion, as shown below.

Interpretation:

UPEE <2.0 g/day —> Within normal limits

UPEE 2.0–3.5 g/day —> Above normal limit - investigate further

UPEE >3.5 g/day —>Nephrotic range

Nephrotic vs Nephritic

Remember to always think of nephrotic syndrome in contrast to nephritic syndrome! I love this image:

Workup

1.

Make the diagnosis: urinalysis, urine protein, urine creatinine, serum albumin, a lipid panel, basic metabolic panel

2. Consider further testing to differentiate primary vs secondary on a case-by-case basis: HIV, ANA, complement (C3/C4 and total hemolytic complement), serum free light chains and urine protein electrophoresis and immunofixation, syphilis serology, hepatitis B and hepatitis C serologies, and the measurement of cryoglobulins; when in doubt, run it by nephrology

3. Consider testing for complications: POCUS for pleural effusion/ascites; CXR for pleural effusion, dopplers or CTA for venous thromboembolism; antithrombin III, plasminogen, protein S (hyper coagulability); immunoglobulins; 

3. Usually renal biopsy is required for definitive diagnosis

Etiology/Treatment/Dispo

In children 10 years or younger, it is minimal change disease (MCD) 90% of the time. Most MCD responds to corticosteroids.

In children >10 years, it is MCD >50% of the time.

In adults focal segmental glomerulosclerosis (FSGS) is the most common etiology (35%). It can be primary/idiopathic, or associated with other disease processes, most commonly HIV or massive obesity.

In most cases, a biopsy will be needed in order to confirm diagnosis.

Admit patients with severe edema, pulmonary effusions or respiratory symptoms, or signs and symptoms suggestive of systemic infection or thrombotic complications to the hospital.

Discharge with nephrology follow up ASAP and low salt diet if only mild-moderate edema.

In kids age 1-10, may consider starting a course of steroids (

Prednisone 2 mg/kg/day x 6 wks then 1.5 mg/kg every other day x 6 wks) only if:

• Age 1-10

• No renal insuficiency

• No macroscopic hematuria

• No sx systemic disease

• No HTN

• Normal C3 levels

Special scenarios

Nephrotic syndrome + chest pain?

DDX: PE and myocardial ischemia because hyperthrombotic, pneumonia (immunosuppressed), pleural effusion

Consider POCUS, CXR, CTA, EKG, cardiac enzymes

Severe edema:

Requires lasix

May need albumin infusion prior to lasix if anasarca or signs of intravascular depletion

Hopefully you’ve already consulted ICU if you’re having to do this

Significant hypertension:

ACEi or ARB

SBP/Empyema:

Pleural effusions/ascites are common in severe fluid overload

Both are extra susceptible to infection in this state

Low threshold for diagnostic paracentesis/thoracentesis

References

Uptodate: Overview of heavy proteinuria and the nephrotic syndrome

Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e: Chapter 134: Renal Emergencies in Children

Michael Mojica, MD. “PEM Guides.” NYU Langone Medical Center, 2015. iBooks. 

https://itunes.apple.com/us/book/pem-guides/id1039923332?mt=11

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