Uroscopic rainbow: modern matula medicine

The Effects of Diet, Dietary Supplements, Drugs and Exercise on Physical, Diagnostic Values of Urine Characteristics

Background/Objectives: This review summarizes the current knowledge about factors that affect the physical characteristics of urine. It highlights proper urine sample collection and displays factors like diet, hydration status, and medications that can alter urine color, odor, clarity, specific gravity and pH. Results: Urinalysis is a minimally invasive examination of a patient's health, especially concerning nephrological and endocrinological abnormalities, as well as dietary habits and stimulants used. Certain deviations in appearance, composition or frequency/pain during urination may indicate an ongoing disease process in the body. Based on laboratory results, further medical treatment is determined. The reason for a change in the color of the urine, for its clouding or intense odor may be a disease, as well as the consumption of food, medication, intensive physical exercise or inadequate hydration of the body. Well-standardized procedures for collecting, transporting, preparing and analyzing samples should become the basis for an effective diagnostic strategy in urinalysis. It is worth noting that pharmacists in pharmaceutical care are often the first people to whom a patient turns for health advice and for the interpretation of simple laboratory tests. Acquiring the ability to interpret the results of laboratory tests and the principles of proper sampling for laboratory tests is indispensable in the process of possible counseling and providing reliable answers to patients' questions. Conclusions: Although urinalysis is not recommended as a routine screening tool for the general population, it can prove to be a valuable source of patient health data in some cases as the data will be useful to physicians and pharmacists to more effectively diagnose and better care for patients.

Alkaptonuria

Alkaptonuria is a rare inborn error of metabolism caused by the deficiency of homogentisate 1,2-dioxygenase activity. The consequent homogentisic acid (HGA) accumulation in body fluids and tissues leads to a multisystemic and highly debilitating disease whose main features are dark urine, ochronosis (HGA-derived pigment in collagen-rich connective tissues), and a painful and severe form of osteoarthropathy. Other clinical manifestations are extremely variable and include kidney and prostate stones, aortic stenosis, bone fractures, and tendon, ligament and/or muscle ruptures. As an autosomal recessive disorder, alkaptonuria affects men and women equally. Debilitating symptoms appear around the third decade of life, but a proper and timely diagnosis is often delayed due to their non-specific nature and a lack of knowledge among physicians. In later stages, patients' quality of life might be seriously compromised and further complicated by comorbidities. Thus, appropriate management of alkaptonuria requires a multidisciplinary approach, and periodic clinical evaluation is advised to monitor disease progression, complications and/or comorbidities, and to enable prompt intervention. Treatment options are patient-tailored and include a combination of medications, physical therapy and surgery. Current basic and clinical research focuses on improving patient management and developing innovative therapies and implementing precision medicine strategies.

Turquoise Urine in a Man Who Had Urinary Retention

While distressing to patients and physicians alike, urine discoloration is mostly benign. Most cases are due to food and drugs. A thorough history and physical exam generally elucidate the etiology but clinicians should have a broad knowledge of the differential diagnosis because life-threatening conditions, such as infection and poisonings, can also manifest as urine discoloration. Here, we present a case of a patient who presented with urinary retention and was found to have turquoise-colored urine, which was due to one of the patient's medications, Uribel. An appreciation of urine discoloration that is related to a benign and reversible medication can lead to stress reduction for patients and a reduction in unnecessary additional testing.

Urine color expressed in CIE L*a*b* colorspace during rapid changes in hydration status

Background

To investigate how rapid changes in hydration affect urine color expressed in CIE L*a*b* colorspace.

Methods

This study was a two-day crossover design where subjects (N = 30) came in one visit dehydrated, after a 15 h overnight fluid deprivation, and rapidly rehydrated by drinking at least 1000 mL of water in 2 h. On the other visit subjects reported euhydrated and then rapidly dehydrated 2% by walking (3 mph) in a heat chamber (100°F, 50% humidity) for 2 h. Urine samples on both days were collected pre- and post-dehydration/rehydration. Urine osmolality, urine specific gravity, subjective urine color and objective urine color expressed in CIE L*a*b* colorspace were measured.

Results

In the dehydration trial participants experienced a significant weight loss of approximately 2% of their starting, euhydrated body weight. The CIE urine color L*-value significantly decreased (−2.3 units) while the b*-value significantly increased (16 units). Subjective urine color significantly increased (1 unit). Urine osmolality increased (25 mmol/kg) and urine specific gravity increased (0.002 g/mL) between the pre- and post-dehydration conditions, however, neither of these changes were statistically significant. In the rehydration trial participants had a significant 1.5% increase in body weight after the ingestion of water. Significant increases were observed in the CIE urine color L*-value (7 units) and a*-value (1.1 units), while the b*-value significantly decreased (−24 units). Subjective urine color significantly decreased (−3 units). Urine osmolality (−600 mmol/kg) and urine specific gravity (−0.018 g/mL) significantly decreased between the pre- and post-rehydration conditions.

Conclusions

Traditional markers of hydration, including urine osmolality and urine specific gravity, did not significantly change in the acute dehydration trial, suggesting that these values may not be responsive to rapid changes in hydration status. However, the CIE L*- and b*-values of urine color significantly decreased in the rapid dehydration trial and significantly increased in the rapid rehydration trial. Thus, the results of the current study suggest that urine color L*- and b*-values expressed in the CIE L*a*b* colorspace were more responsive to changes in hydration status during rapid dehydration than traditional indices of urine concentration and thus may be better markers under such conditions.

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Rapid dehydration significantly increases both subjective and objective urine color.

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Rapid rehydration significantly decreases both subjective and objective urine color.

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CIE L*a*b* colorspace quantifies urine color to better assess hydration status during rapid dehydration.

Analysis of the Distribution of Urine Color and Its Relationship With Urine Dry Chemical Parameters Among College Students in Beijing, China - A Cross-Sectional Study

Objectives: The objective of this study was to provide a new classification method by analyzing the relationship between urine color (Ucol) distribution and urine dry chemical parameters based on image digital processing. Furthermore, this study aimed to assess the reliability of Ucol to evaluate the states of body hydration and health.

Methods: A cross-sectional study among 525 college students, aged 17–23 years old, of which 59 were men and 466 were women, was conducted. Urine samples were obtained during physical examinations and 524 of them were considered valid, including 87 normal samples and 437 abnormal dry chemistry parameters samples. The urinalysis included both micro- and macro-levels, in which the CIE L^*a^*b^* values and routine urine chemical examination were performed through digital imaging colorimetry and a urine chemical analyzer, respectively.

Results: The results showed that L^* (53.49 vs. 56.69) in the abnormal urine dry chemistry group was lower than the normal group, while b^* (37.39 vs. 33.80) was greater. Urine color can be initially classified based on shade by grouping b^*. Abnormal urine dry chemical parameter samples were distributed more in the dark-colored group. Urine dry chemical parameters were closely related to Ucol. Urine specific gravity (USG), protein, urobilinogen, bilirubin, occult blood, ketone body, pH, and the number of abnormal dry chemical parameters were all correlated with Ucol CIE L^*a^*b^*; according to a stepwise regression analysis, it was determined that more than 50% of the variation in the three-color space values came from the urine dry chemical parameters, and the b^* value was most affected by USG (standardized coefficient β = 0.734, p < 0.05). Based on a receiver operating characteristic curve (ROC) analysis, Ucol ≥ 4 provided moderate sensitivity and good specificity (AUC = 0.892) for the detection of USG ≥ 1.020.

Conclusions: Our findings on the Ucol analysis showed that grouping Ucol based on b^* value is an objective, simple, and practical method. At the same time, the results suggested that digital imaging colorimetry for Ucol quantification is a potential method for evaluating body hydration and, potentially, health.

The Effect of Hydration on Urine Color Objectively Evaluated in CIE L*a*b* Color Space

Urine color has been shown to be a viable marker of hydration status in healthy adults. Traditionally, urine color has been measured using a subjective color scale. In recent years, tristimulus colorimetry developed by the International Commission on Illumination (CIE L^*a^*b^*) has been widely adopted as the reference method for color analysis. In the L^*a^*b^* color space, L^* indicates lightness ranging from 100 (white) to 0 (black), while a^* and b^* indicate chromaticity. a^* and b^* are color directions: –a^* is the green axis, +a^* is the red axis, –b^* is the blue axis, and +b^* is the yellow axis. The L^*a^*b^* color space model is only accurately represented in three-dimensional space. Considering the above, the purpose of the current study was to evaluate urine color during different hydration states, with the results expressed in CIE L^*a^*b^* color space. The study included 28 healthy participants (22 males and 6 females) ranging between the age of 20 and 67 years (28.6 ± 11.3 years). One hundred and fifty-one urine samples were collected from the subjects in various stages of hydration, including morning samples after 7–15 h of water deprivation. Osmolality and CIE L^*a^*b^* parameters were measured in each sample. As the urine osmolality increased, a significant linear increase in b^* values was observed as the samples became more pronouncedly yellow (τ_b = 0.708). An increase in dehydration resulted in darker and significantly more yellow urine, as L^* values decreased in lightness and b^* values increased along the blue–yellow axis. However, as dehydration increased, a notable polynomial trend in color along the green–red axis was observed as a^* values initially decreased, indicating a green hue in slightly dehydrated urine, and then increased as urine became more concentrated and thus more dehydrated. It was determined that 74% of the variance seen in urine osmolality was due to CIE L^*a^*b^* variables. This newfound knowledge about urine color change along with the presented regression model for predicting urine osmolality provides a more detailed and objective perspective on the effect of hydration on urine color, which to our knowledge has not been previously researched.

Purple urine bag syndrome: An unusual but important manifestation of urinary tract infection. Case report and literature review

Purple urine bag syndrome is a rare albeit alarming purple discolouration of the urine typically seen in elderly ladies with constipation, urinary tract infection and concurrent urinary catheterisation. In this concise review, we report the pathophysiology of this condition and the case of one patient who developed this interesting phenomenon.

Black Coloured Urine following Organophosphorus Poisoning: Report of Two Cases

Organophosphorus poisoning is common in rural Asia. Clinical features result from overactivity of acetylcholine receptors. Blackish discoloration of urine is not a feature of organophosphorus poisoning. Only one case of black colored urine following quinalphos poisoning has been reported in literature. We report two cases of organophosphorus poisoning from two different compounds, following which patients passed black colored urine, in the absence of haemolysis or rhabdomyolysis. These cases indicate that blackish discoloration of urine in organophosphorus poisoning might not be as uncommon as it was believed to be. Besides, urinary excretion of metabolites might be an underlying mechanism, rather than hemolysis.

Unusual complications of quinalphos poisoning

This 40-year-old man was treated for suicidal quinalphos 25%EC consumption. He developed intermediate syndrome with normal response to repetitive nerve stimulation, pancreatitis with high enzyme elevations, and normal computed tomography and excreted black, brown, and orange urine sequentially over the first nine days of hospitalization. The last complication has not been previously reported with any organophosphate compound. He finally succumbed to complication of ventilator associated pneumonia related septic shock and ventricular tachycardia.

Urine bag as a modern day matula

Since time immemorial uroscopic analysis has been a staple of diagnostic medicine. It received prominence during the middle ages with the introduction of the matula. Urinary discoloration is generally due to changes in urochrome concentration associated with the presence of other endogenous or exogenous pigments. Observation of urine colors has received less attention due to the advances made in urinalysis. A gamut of urine colors can be seen in urine bags of hospitalized patients that may give clue to presence of infections, medications, poisons, and hemolysis. Although worrisome to the patient, urine discoloration is mostly benign and resolves with removal of the offending agent. Twelve urine bags with discolored urine (and their predisposing causes) have been shown as examples. Urine colors (blue-green, yellow, orange, pink, red, brown, black, white, and purple) and their etiologies have been reviewed following a literature search in these databases: Pubmed, EBSCO, Science Direct, Proquest, Google Scholar, Springer, and Ovid.

Urine as a specimen to diagnose infections in twenty-first century: focus on analytical accuracy

Urine as a clinical specimen to diagnose infections has been used since ancient times. Many rapid technologies to assist diagnosis of infections are currently in use. Alongside traditional enzyme immunoassays (EIA), new technologies have emerged. Molecular analysis of transrenal DNA to diagnose infections is also a rapidly growing field. The majority of EIAs utilize the detection of excreted sugar compounds of the outer microbial cell-wall shed into the bloodstream and excreted into the urine. This mini-review focuses on current knowledge on rapid urinary antigen detection tests to diagnose most common infections, and highlights their diagnostic utility. The past and the future of urinalysis are also briefly discussed. The analysis of the literature shows that some methods are not quantitative, and analytical sensitivity may remain suboptimal. In addition, the performance criteria and technical documentation of some commercial tests are insufficient. Clinical microbiologists and physicians should be alert to assay limitations.