Acquired dermal macular hyperpigmentation: an overview of the recent updates

Acquired dermal macular hyperpigmentation (ADMH), previously known as macular pigmentation of uncertain etiology (MPUE), is an umbrella concept that unifies the distinct but overlapping acquired dermal pigmentary disorders like lichen planus pigmentosus, ashy dermatosis, erythema dyschromicum perstans, Riehl's melanosis and pigmented contact dermatitis. All of these disorders usually lack a clinically apparent inflammatory phase, are characterised by dermal pigmentation clinically and histologically, and have a variable protracted disease course. Recently, a proposal has been made to classify these disorders into those with and without contact sensitisation. Dermoscopy is essentially similar across the spectrum of these disorders, and is useful for diagnosis and therapeutic response monitoring. Scoring system has been validated for the same. The treatment of ADMH remains challenging, with multiple topicals, oral therapies including mycophenolate mofetil, and lasers tried. Need of the hour is randomised controlled trials to enhance the therapeutic armamentarium.

X-Linked Reticulate Pigmentary Disorder

This case report describes a child with generalized reticulate hyperpigmentation and recurrent pneumonia, hypohidrosis, photophobia, and diarrhea.

Skin hyperpigmentation index in melasma: A complementary method to classic scoring systems

BACKGROUND

Due to relapsing nature of melasma with significant impact on quality of life, an objective measurement score is warranted, especially to follow-up the patients with melasma and their therapy response in a quantitative and precise manner.

AIMS

To prove concordance of skin hyperpigmentation index (SHI) with well-established scores in melasma and demonstrate its superiority regarding inter-rater reliability. Development of SHI mapping for its integration in common scores.

METHODS

Calculation of SHI and common melasma scores by five dermatologists. Inter-rater reliability was assessed by intraclass correlation coefficient (ICC) and concordance by Kendall correlation coefficient.

RESULTS

Strong concordance of SHI with melasma area and severity index (MASI)-Darkness (0.48; 95% CI: 0.32, 0.63), melasma severity index (MSI)-Pigmentation (0.45; 95% CI: 0.26, 0.61), and melasma severity scale (MSS) (0.6; 95% CI: 0.42, 0.74). Using step function for mapping SHI into pigmentation scores showed an improvement of inter-rater reliability with a difference in (ICC of 0.22 for MASI-Darkness and 0.19 for MSI-Pigmentation), leading to an excellent agreement.

CONCLUSION

Skin hyperpigmentation index could be an important additional cost-and time-conserving assessment method, to follow-up the patients with melasma undergoing brightening therapies in clinical studies, as well as in routine clinical practice. It is in strong concordance with well-established scores but superior regarding inter-rater reliability.

Phakomatosis Pigmentovascularis: A Rare Disease

A 19-year-old female, Mrs. XYZ, resident of Mumbai came with complaints of fever and cough with whitish expectorate of 12 days duration. The patient had a bright red erythematous patches on bilateral cheeks and chin (Fig. 1). Hyperpigmented patches seen over the body at multiple sites since birth.

Seasonal Patterns in Tetracycline-Associated Hyperpigmentation Among Patients With Acne Vulgaris

BACKGROUND

Oral tetracyclines (TCNs) are commonly prescribed for acne, but they have been shown to increase the risk of hyperpigmentation, particularly in the setting of sun exposure.

OBJECTIVE

We evaluated seasonal trends in TCN-associated hyperpigmentation incidence in addition to Google search trends for hyperpigmentation-related terms.

METHODS

We performed a retrospective review of acne patients seen at Massachusetts General Brigham and Women’s Hospital between 1992 and 2022. We calculated the incidence of new hyperpigmentation diagnoses for each drug cohort. We also analyzed search volume of hyperpigmentation-related terms extracted from Google Trends.

RESULTS

Seasonal differences in new hyperpigmentation diagnoses were identified among acne patients prescribed doxycycline (P=0.016), with peak incidence in April. In the control group of patients who had never received a TCN, diagnoses peaked in May. There were no significant seasonal differences among patients prescribed minocycline (P=0.885). There was greater search volume for hyperpigmentation-related terms in spring and summer compared to fall and winter (P<0.001). Limitations of this study include its retrospective nature and reliance on prescription and diagnosis coding data.

CONCLUSIONS

Our findings support the seasonal periodicity of acne-related hyperpigmentation, underscoring the importance of photoprotection counseling for patients with acne. Additionally, doxycycline may be associated with an earlier onset of hyperpigmentation, suggesting a potential benefit of considering minocycline or other alternatives to doxycycline. J Drugs Dermatol. 2023;22(11):e9-e11    doi:10.36849/JDD.7409e.

Dyschromatosis universalis hereditaria

Reticulate pigmentary dyschromatoses primarily include dyschromatosis universalis hereditaria (DUH), dyschromatosis symmetrica hereditaria (DSH) (Reticulate acropigmentation of Dohi), and unilateral dermatomal pigmentary dermatosis, which differ in their patterns of distribution. The disease was initially described by Ichikawa and Hiraga in Germany in 1933. The prevalence of DUH is 0.3 per 100,000 with a female preponderance. The skin lesions usually appear in infancy or early childhood and cease to progress beyond adolescence. The subtypes DUH 1 and DUH 3 are found to have autosomal dominant inheritance, which is the most common inheritance pattern, while DUH 2 has an autosomal recessive pattern. The most common gene involved in DUH is ABCB6, while the other genes include SASH 1, PER 3, and KITLG (DUH type 2). DUH is characterized by multiple irregular hyperpigmented macules interspersed with hypopigmented macules in a mottled pattern over the trunk and extremities. The face is involved in 50% of individuals. Rarely, it can also involve hairs, nails, mucous membranes, palms, and soles. Other varied presentations include localized forms, localization of lesions to sun-exposed areas, large macules, uniform palmar hypopigmentation, diffuse hyperpigmentation with spotty depigmented macules, and unilateral involvement. DUH has been reported to be associated with various cutaneous and systemic diseases. The authors have observed cases of DUH associated with hepatocellular carcinoma, solitary keratoacanthoma, and dermoid cyst. The various diagnostic modalities include dermoscopy, histopathology, electron microscopy, and targeted gene sequencing. Though various treatment modalities like NBUVB and lasers have been tried, no treatment is promising.

Reticular melanonychia: a dermoscopic clue for terra firma-forme dermatosis on the nails

Terra firma-forme dermatosis of the nail plate can mimic other causes of melanonychia such as nail infection and melanoma. We present the cases of two patients and describe the dermoscopic features of this entity, which is characterized by a band-like reticular pigmentation that we describe as ‘reticular melanonychia’.

Retyping and molecular pathology diagnosis of dyschromatosis universalis hereditaria

Dyschromatosis universalis hereditaria (DUH) is characterized by diffuse symmetrically distributed hypopigmented macules mixed with hyperpigmentation. DUH is divided into three types by Online Mendelian inheritance in man (OMIM) that is, DUH1 (OMIM 127500), DUH2 (OMIM 612715) and DUH3 (OMIM 615402) according to the different linkage regions. Although each condition possesses corresponding phenotypic characteristics and the prognosis for each is somewhat different, these disorders are highly overlapped and difficult to differentiate in the clinical setting. Our latest study reveals a novel DUH subtype that presents a mild phenotype of pigmentation anomalies and is named PER3rs772027021 SNP related DUH or DUH4 by us, which make the DUH subtype can be further retyped. Heterozygous distribution or mosaic-like distribution of melanin is a newly discovered pathological features that is uniquely demonstrated in the affected layers of DUH1 and DUH4 patients. In this review, DUH is further divided into four subtypes according the causative genes and their mutational sites, and the mutation regions described in the previous reports. To make an accurate diagnosis, we suggest that Sanger sequencing or the target region sequencing (TRS) to the candidate causative genes related melanogenesis may be the most effective and convenient method of clinical diagnosis or/and prenatal diagnosis for DUH and DUH-like patients. More importantly, heterozygous distribution or mosaic-like distribution of melanin can be utilized for differential diagnosis of DUH. We also investigate the underlying molecular mechanism to form mosaic-like melanin in the affected layers of hyper- and/or hypo-pigmented macules from DUH1 and DUH4 patients. This review provides a molecular and pathological delineation of four types of DUH and aims to establish a concise diagnostic strategy to allow clinical dermatologists to make an accurate diagnosis.

Brief report: Areolar melanosis in a girl with precocious puberty

We report a case of melanosis of the areola in a 7-year-old girl with early thelarche. Areolar melanosis is a rare condition previously only described in women over 25 years of age, often in the setting of pregnancy. This case supports a theory that hyperpigmentation may be associated with increased sensitivity to hormonal stimulation in areas with greater populations of melanocytes.

[Eritema pigmentado fijo secundario a AINE: Reporte de caso]

Background

Fixed erythema pigmento (FPE) is an allergic drug reaction, the pathophysiology of which is not exactly known. It is more common in women with location on the face. Clinical presentation: round or oval red-purple macule, well defined, with swelling, pain, itching, and burning. Diagnosis is clinical, oral chal- lenge is contraindicated due to possible severe reaction. On withdrawal of the drug, residual violaceous hyperpigmentation remains.

Case report

34-year-old female diagnosed with allergic rhinitis and asthma. She received treatment with ibuprofen and cephalexin 1 month ago due to dental infection. For the past 2 weeks, she has presented dermatological lesions characterized by hyperpigmentation under the lower eyelids, accompanied by pain, burning, and itching. On physical examination, well-defined red-purple pigmentation was observed in both periocular regions. The challenge test is not justified, the clinical history is the diagnostic pillar. The indication is to stop the medication immediately and continue monitoring.

Conclusions

EPF is a drug reaction related to drug use. It creates a challenge for diagnosis due to poor knowledge of the characteristics of the dermatosis and poor clinical and pharmacological questioning. The EPF approach requires knowing the clinical characteristics of this dermatosis, making a differential diagnosis with other lesions and indicating the suspension of the responsible medication.

Penile terra firma-forme dermatosis in children

Terra firma-forme dermatosis (TFFD) is a rare, acquired keratinization disorder that predominantly affects children and young adults. Herein, we report three unusual cases of penile TFFD in children and the histopathologic and ultrastructural observations.

Disorders of hyperpigmentation. Part I. Pathogenesis and clinical features of common pigmentary disorders

Disorders of hyperpigmentation are common and, depending on the extent and location of involvement, can affect the quality of life and pose a significant psychologic burden for patients. Given the similarities in presentation of the various causes of hyperpigmentation, it is often difficult to elucidate the etiology of these conditions, which is important to guide management. Furthermore, certain disorders, such as lichen planus pigmentosus and ashy dermatosis, have similar clinical and/or histologic presentations, and their classification as distinct entities has been debated upon, leading to additional confusion. In this review, the authors selected commonly encountered disorders of hyperpigmentation of the skin, subdivided into epidermal, dermal, or mixed epidermal-dermal disorders based on the location of pigment deposition, along with disorders of hyperpigmentation of the mucosa and nails. Melanocytic nevi, genetic disorders, and systemic causes of hyperpigmentation were largely excluded and considered to be outside the scope of this review. We discussed the pathogenesis of hyperpigmentation as well as the clinical and histologic features of these conditions, along with challenges encountered in their diagnosis and classification. The second article in this 2-part continuing medical education series focuses on the medical and procedural treatments of hyperpigmentation.

Acute Onset Linear Lichen Planus Pigmentosus of the Forehead: A Case Series

Linear lichen planus pigmentosus (LPP) of the face is a rare variant of lichen planus, with only a few cases published in the literature.1 It is an inflammatory condition with unknown etiology, characterized by blue-gray hyperpigmented macules, and tends to affect sun-exposed areas of the head and neck.1-4 The pathophysiology of linear lichen pigmentosus is poorly understood, though it is postulated to be caused by T-lymphocyte autoimmunity against keratinocytes.5-7 LPP more frequently affects middle age woman and skin phototypes III-VI.1,3 Treatment for linear LPP is difficult and there is no established first-line therapy; however, tacrolimus ointment, topical corticosteroids, and various systemic agents have shown to be effective in improving the appearance.3,8,9 Prior reports have characterized linear LPP that follows the lines of Blashko as more commonly affecting the trunk.1 We present three cases of linear lichen planus pigmentosus (LPP) of the forehead, a unique novel presentation of linear LPP of the face. One of our cases also provides supporting evidence for tacrolimus to be used as a preferred therapy to treat linear LPP of the face; however, more research is needed to support this claim. To our knowledge, this case series is the largest case series of linear lichen planus pigmentosus (LPP) of the forehead to be reported. J Drugs Dermatol. 2023;22(1):94-97. doi:10.36849/JDD.7200.

Blue-black hyperpigmentation on the extremities

In some cases, diagnosis entails less "what is it?" and more "what caused it?"